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Why are we taller than our ancestors?
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Better nutrition is a good start. Compare the average height in South Korea with the average height in North Korea . And that's after just half a century of malnutrition. Not sure about the rest, but the importance if better nutrition cannot be overstated here. I can imagine there's been some evolutionary selection in mates favoring taller, stronger, healthier-looking people, as well, but that depends on how far back you go to define "ancestors."Better nutrition and less time spent fighting infections and diseases, which hinder growth. We now have vaccines, antibiotics, pest control, reduced endemic diseases, parasites control, so on. _URL_0_', "It's a combination of environmental factors and genetic factors, driven mostly by natural selection and genetic drift . Over time, taller people had an advantage over shorter people, they had improved chances of surviving and reproducing and so over time, people on average became taller.
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How does flea medication for pets work?
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Almost all modern flea meds are insect neurotoxins that effect receptors that mammals do not have. It depends on the treatment but imidacloprid , indoxacarb and Fipronil are dispersed over the body by natural skin oils and muscle movements. This can take 24-48 hours to happen completely. This is also why you should not bathe your animal with detergent soap during the month. The medications ARE NOT systemically absorbed. This is why there are over the counter. Selemectin is systemically absorbed and works from that direction The orals are obviously systemic Sentinal/Program is systemic, but acts very differently. These are insect growth regulators and prevent chitenization. This keeps early life stages of the flea from developing. Think "birth control" for fleas. It does not kill the adult flea. Source: Veterinarian 12 years Veterinary industry 23The shoulder blade spot-on treatments are absorbed through the skin, go into the blood, and are then ingested by the adult fleas when they bite the animal. The best flea treatments generally have two active ingredients. There is the "adulticide" which kills the biting adults, and also an insect growth regular that suppresses eggs/larvae/pupae. I believe some preparations are meant to be applied to the whole fur, and have a local killing effect.I have no authority on this matter
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What gives the federal government the right to ban marijuana? And why can states violate that? [Serious]
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The Commerce Clause of the Constitution gives Congress the authority to regulate items that have a high probability of being trafficked across state borders. States that have chosen to legalize marijuana are simply choosing not to enforce federal marijuana laws and have gotten rid of most of their own criminal & civil penalties on the sale and trafficking of the drug. If the federal government wants to enforce those laws they now must carry out enforcement itself. Prohibition was put through as a Constitutional Amendment because proponents felt it would be a more permanent change than a simple law that could easily be overturned. Remember when Prohibition passed no Amendment had ever been overturned at that pointThe way I see it, when a state goes against a federal law it means the people of the state are actively trying to veto the law, but can only do so on a state level. There needs to be a bigger and clearer distinction of what the federal powers are and what the state power are. Too much damn ambiguity in our governmentAs an outsider not really familiar with US laws, do I get it right from the explanations, that in simple terms the local police won't enforce the federal law , but if the F.B.I comes knocking, they can arrest/convict you?Are there any "big" laws like this one, where the difference in federal and state law is treated "lighlty"?
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Why did Britain and France declared war on Germany over the invasion of Poland, but not the USSR?
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Although the English and French were not on the best terms with the Soviet Union, the Soviets had not been acting aggressively for the last few years, unlike the Germans. Before the Polish invasion, the Germans broke the Treaty of Versailles, militarized the Rhineland, annexed Austria, invade the Sudetenland , and then the rest of Czechoslovakia. The British and French had a valid cause to declare war on Germany for each of these transgressions, but they didn't. The final act that finally pushed the world into war was the German invasion of Poland. The Soviet invasion of western Poland was their first act. The English and French had to no agreement to protect Poland from the Soviet Union, nor did they warn the Soviet Union against expansion, nor was the Soviet Union bound by treat not to take up arms. Also, fighting a war against Germany made geographic sense, but not a war against the Soviet Union. The soldiers could attack Germany from France with support from across the English channel. However, attacking the Soviet Union would first require going through German, then through Poland, and into the heart of Russia. The English and French did not want to go to war at all, so spreading themselves across Europe was not going to happen. In fact, the English and French did do anything during the Polish invasion, which showed how unwilling they were to fight at that point in time.
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How hard is it for a horse to carry a human? And what would be the equivalent for a human?
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From what I've found it looks like an average horse can easily carry about 240 pounds. It can carry up to around 360 pounds with some effort, and over that only with considerable strain. So a horse carrying an average-sized person would be within that easy weight. Another quick search shows that around the maximum recommended backpacking weight for humans is around 1/3 of body weight. Which is around where the horses really start to struggle. So for the comparison, just imagine a very heavy backpack as about the maximum a horse could take . An easy weight to just walk around would be around around 200 pounds for a horse, or around 30 pounds for a person.
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Google acquiring Motorola Mobility.
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There may be real implications, but current consensus in the tech and business communities is that this is just another salvo in the ongoing patent "war" between the major tech giants. Companies like Google, Apple, Microsoft, Oracle, and a few others are snatching up patents left and right, and paying lots of money for them. The idea is that, by controlling certain patents, one company can prevent the rest from using that technology. Moreover, if they do use it, they can be sued for patent infringement. There are currently many such lawsuits in various stages between Apple, HTC, Google, Nokia, and a couple other companies. The stakes are pretty high - we're talking billions of dollars. One could even argue that these patent purchases are investments, because if you win a lawsuit with them then you get a lot of money. It's basically a massive land grab, but with intellectual property. Edit - ELI5 addendum: A **patent** is when you come up with a new idea or product, and you tell the government about it. The government will guarantee you that no one else is allowed to copy your idea for a certain amount of time. This is so you can be rewarded for your great new idea. If you came up with a new recipe for lemonade that was twice as delicious, you wouldn't want every kid on the block setting up a lemonade stand with your new recipe, would you?
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what is a kardashev civilization?
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Kardashev created a loose scale to describe hypothetical civilizations based on how much energy they could harness, as energy harnessed roughly translates to work that can be achieved and people that can be supported. A Kardashev-1 civilization is capuring the full energy potential of their planet. A K2 civilization is capturing the full energy potential of their solar system A K3 civilization is capturing the full energy potential of their galaxyIt comes from the **Kardashev scale**, which was created by a soviet astronomer named Nikolai Kardashev for rating the technological progress of hypothetic advanced civilizations. A type 1 Kardashev civilisation would be one that was able to harvest all the solar energy reaching its planet from the star it orbit, for use in powering stuff. The earth is heated up by sunlight for example, but a lot of this light is just reflected back into space. If we could create some way of preventing any light from leaving the earth's atmosphere once it enters it, and turn it into usable power, we 'd be a type 1 civilisation The same concept is repeated as one goes up the scale, just bigger. A type 2 civilisation is able to trap and use all the light from a star, not just the light hitting a single planet. This would likely involve completely enclosing the solar system in a "Dyson sphere" so that no light can escape it. A type 3 civilization is the same concept, only expanded to an entire galaxy. The scale is mainly used in science fiction, since even becoming a type 1 civilisation is an engineering challenge far beyond the current capability of humanityIf you have ever seen the manga Blame!, that is an example of a K1 bordering on K2 civilizeation
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Why did the Roman Empire get divided?
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The first split came in CE 285 when the emperor Diocletian decided that the Roman empire had become too large to be effectively ruled by one man. He split the empire into West and East, keeping the eastern part for himself because it was richer in goods and trade. In the western part he appointed Maximian, who was in theory equal to Diocletian but in reality subject still to Diocletian. After a civil war across both parts of the empire that started in 306. In 314, Constantine claimed ultimate victory and reunited the Empire under a single ruler. He did however move the capitol to Constantinople [modern day Istanbul, Turkey] in the eastern part. In 337 Constantine died and civil war erupted between his three sons, who divided the empire into three different parts. Valentinian emerged as victor and single leader in 364. He immediately divided the empire again, giving the eastern half to his brother Valens. Succession rebellions in the west eventually forced the Eastern emperor Theodosius I to quell the rebellions and become a single ruler of a unified Roman empire again. He was however the last emperor to rule both East and West. After his death in 395, his two sons inherited the East and West respectively. This was the final and permanent division of the Roman empire. The Western half wouldn't last long, finally falling in 476 with the sack of Rome. The Eastern half would exist another 1000 years, becoming known as the Byzantine empire. So it was too big to be ruled by 1 man.
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How supplements are not drugs and drugs are not supplements
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It entirely depends upon whether that particular substance has been put through the rigorous multi-year testing required by the US Food and Drug Administration to prove that said substance does actually help or cure the condition the company claims it does . That process is Hella fucking expensive, and if a company can avoid it, it does, because prefer to make as much dough as possible, without being bothered by pesky things like prosecution for wrongful deaths. So if a company sells a substance as a supplement, they ain't gotta do any testing. This doesn't save them from prosecution if people die, though. And if enough people complain, the FDA will get 'em on false advertising anyway
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Why was the Irish potato famine such a big deal? Didn't they have other foods they could eat?
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Ireland produced enough food during the famine, but it was seized by/owed to the English. The potato famine was less of a natural famine, and more of a genocide. Similar things happened to the Ukrainians at the hands of the Soviets during the HolodomorMost of Ireland was incredibly poor and engaged in subsistence farming . The potato was by far the best way to do this for a few reasons. First, potatoes could easily be grown in small patches like in a small yard. Second, potatoes can be eaten without much preparation, unlike something such as wheat, which has to be milled first. Third, potatoes are calorie-rich. You can get about three times as many calories per acre out of potatoes than you can wheat and about 50% more than you can from corn. All of this adds up to make potatoes by far the easiest thing to grow for poor Irish peasants. When those potatoes started dying and there was literally no other source of food, people either had to flee or starve. Edit: /u/evange is also correct. The reason poor Irish peasants were so poor and had to rely on subsistence farming potatoes is due to British land seizures and unfair economic policy. So Ireland had enough food for everyone, but potatoes were the only food accessible to a large portion of the population because of British policies.A large part of it was that that single strain of potato made up a third of the national crop, but a bigger part was english colonial laws. Even though there was a massive famine, the British still forced the Irish to export millions of tons of food. While that at least had an economic component to it, the English also banned any and all food donations to the Irish, because the English hated the Irish and just felt like there were too many Irishmen in the world. I don't like labeling anything as good or evil, but that policy was hitler-evil.
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If many states have no laws regarding age of tattoo with parental constant. How is it not considered child endangerment/neglect to allow your 6 year old to get a tattoo?
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The same way it is not considered child endangerment/neglect to allow your 6 year old to see a rated R movie. Just because something has an age range does not make its particularly dangerous for people under that age
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How dry ice is made
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Once you cool Carbon Dioxide, a gas at room temperature, enough, it becomes a liquid, and, after even more cooling, it becomes a solid, which is basically just dry ice. When the dry ice warms up enough, it returns to the natural gas state, but there's a certain temperature where it's a mist. That's the fog that comes off the ice itself, it's the gas form of carbon dioxide, at a cold enough temperature to still be visible.To make liquids or gasses into solids the basic needs are to lower the temperature and/or increasing the pressure. There may be various different ways that it is made utilizing pressure and temperature changes. You know when you see fire extinguishers discharged and there is that kind of "snow" that ends up on the ground for a little while, this is bits of solid CO2, or dry ice. The fire extinguisher contains liquid CO2 under high pressure, when it is introduced into the atmosphere the pressure drops and the temperature also drops, enough to turn some of that liquid into a solid. One method of making dry ice is basically, in theory, using a giant fire extinguisher. Liquid CO2 is stored under pressure and then is discharged into a sealed low pressure container. The "snow" is then collected and compressed into blocks to make dry ice. The CO2 that was released and did not form "snow" is collected and reused in the same process.
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If Muslims do not believe Jesus died on the cross, what exactly happened to the man?
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My Arabic teacher explained it to me that some Arabs believe that Jesus was a dude and that Christ was a spirit that inhabited him and right before Jesus died Christ left him and went to heaven. And that is why he shouted "why have you forsaken me?" Because he didn't expect Christ to leave him. So Jesus did die on the cross, but the thing/spirit that we think of as "JESUS" didn't. Or something to that effect. But that is definitely not my expertise.I'm not sure what their stance is on the crucifixion. I'm an atheist and while I dunno that it's 100% proven, it seems reasonable to think that Jesus was indeed crucified - we know the man existed, that there was a semi-uprising in Judea around that time, and crucifixion was a common execution method. Not believing he was divine doesn't mean he wasn't crucified.
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Why did the Japanese side with the Germans in WWII?
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I think even the most optimistic of the Germans at the onset of WWII realized that Germany wasn't a big enough country to conquer the entire world. Had Germany won in Russia and western Europe, and Japan not been defeated and eventually secured much of eastern Europe, sure, there's probably a decent chance they would've eventually had some conflict, but sometimes you just need to try and solve the more immediate problems. I would argue that from Japan's point of view, their relationship with Germany helped them pretty significantly in WWII. It made the case for the United States' leadership to focus first on defeating Germany, which gave Japan a couple extra years to try and solidify their position in the pacific. Otherwise, after Pearl Harbor, Japan very well could've been facing the might of the US entirely alone.My history teacher explained it like this:In 1930 Germany the nazis had the opinion that you were a better human being if you were, as the Germans called it, "arisch" or "Herrenrasse" which means something like Master race. That means blonde hair and blue eyes. They saw the Northern Europeans as perfected "arisch". The Japanese apparently hat a similar opinion. They saw them self as the Master race of Asia and are said to agree with a lot of the Nazis opinions. Because of that and because they expected the nazis to be the winning side they decided against siding with the allies.
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why do muscles get better the more you use them
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It's efficient. A pound of muscle burns a dozen or so calories a day, just to sustain itself. By only building the muscles needed for your particular lifestyle, you save a lot of calories that can then be put toward reproduction or not starving. A fisher needs mostly upper body strength, a [persistence hunter]) needs calves of steel, but if everybody got both, they'd waste lot of calories maintaining useless meat. Over a lifetime, a few dozen calories a day can really add up - 77,000 calories gets you an entire extra child .
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Why were the the bodies of those who died of a fatal dose of radiation at the Chernobyl disaster still considered toxic and buried in Zinc lined coffins?
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Two things. First, they probably got radioactive material from the accident site all over themselves. It's not just radiation that's escaping, it's also actual physical radioactive material that can contaminate body and clothes. This what they mean by nuclear fallout. So it's not like a bullet-riddled body, but more like a gun-riddled body, and those guns still shoot occasionally. Second, one specific kind of radiation, neutron radiation, can actually make materials it hits radioactive. Neutron radiation is produced in nuclear reactors, and although it's hard to say whether it'd be still produced after the meltdown, it depends, it's possible that they were exposed to it. Then it'd be more like bullet fragments inside a body growing into loaded guns. Those analogies were unexpectedly gross.Radioactive fallout When Chernobyl exploded it not only sent out massive amounts of radiation but also massive amounts of radioactive material which landed in the surrounding area rendering everything it touched radioactive1. Their skin was contaminated by fallout 2. They may have inhaled radioactive material which will continue to decay 3. Neutron bombardment can cause materials that were not previously radioactive to become radioactive.
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Why do certain policies work in countries such as Sweden and Germany, yet they "apparently" differ in America?
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Yes these systems do work, but it is not possible for america to just switch from private health care is public. It would be like getting England to switch the sides of the road they drive on. It would be unimaginably expensive. Also, many americans think that anything socialized is bad and needs to not happenBecause, implementing those program would require dramatically raising taxation. And that is something which is not exactly popular.
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How are planes able to fly vertically.
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Most planes can't fly straight vertically for any length of time without stalling . The ones that can have *extremely* powerful engines relative to their size, like in fighter jets, which provide so much thrust on their own that they don't need the lift from their wings to maintain their upward momentum.
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Why do you get startled/feel a rush of a adrenaline if you catch yourself falling asleep?
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Are you talking about hypnic jerk ? That feeling where you jerk suddenly back awake sometimes when you're falling asleep? The prevailing theory is this is an evolutionary holdover from our earlier primate days, and is a danger response so our ancestors didn't accidentally fall out of trees.
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Why do delivery truck drivers wear high visibility jackets?
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I would assume it has to do with Health & Safety regulations and legislation, I'm not sure about South Africa but in the UK, Health & Safety dictates that employees working in certain professions need to take certain precautions in their job, one of which could be the need for protective or high visibility clothing. I would imagine truck drivers wear high visibility jackets so that other drivers can see them clearly, being in truck yards and delivery depots, they walk around large vehicles with many blind spots, so to minimize the risk of getting run over they wear clothing that makes them as visible as possible :)
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How can a sample of 2200 people represent the opinions of 315 million.
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Imagine you have a massive jar of M & Ms filled with thousands of pieces. Now if I were to ask you what percentage of them were blue, yellow, brown, and red how do you do it most efficiently? You can dump all of it out and count them one by one but it would take forever. Or you can shake the jar until everything is randomly mixed up and dump out the first one hundred. There's a very good chance, if everything is randomly mixed up, that the percentage of M & Ms in the first hundred has the same distribution as the rest of the thousands of M & Ms. That's essentially how polls are done everywhere. The most difficult part of all this is making sure the sample size is completely random and accurately reflect the rest of the sample.As long as it is a random sample, the probability of the sample having a different opinion than the population drops off very fast with the size of the sample. With 2200 randomly selected people the chance of a significant difference is extremely small for essentially any population size. Good polls will tell you the margin of error and the confidence interval . This is a measure of how far, and how likely, the population might be from the sample. Surveying more people makes these values better but you hit diminishing returns pretty rapidly.
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How does cutting tinfoil with scissors sharpen them?
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This works by cutting several pieces of folded foil. As you cut the top layer of foil that layer is "pushed" sideways by the angle of the blade and rubs along the blade. As you cut more layers the combined pressure of the sheets means the blade is not able to "push" the next layer as sideways, so the next layer presses more firmly against the blade This means that each layer is a little closer to the blade, in a kind of V shape. All these edges scrape up the side of the scissors and scratch away a tiny layer of the metal right up to the edge of the blade. When we remove this tiny layer, we make the blade sharper, like in this diagram: _URL_0_
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- why some materials are more flammable than others.
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In short, yes! When we talk about things "burning", what we actually mean is that the material is combining with oxygen , and releasing heat in the process. Some materials can combine with oxygen easier than others, and usually that is because of their molecular configuration and how their electrons are organized.
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Is there a biological reason why men don't appear as frightened as woman during dangerous situations?
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Men have a lower level of fear response and suffer fewer long-term fear effects than women. [Survey] From a purely sociological standpoint, men further conceal their fear response because it is socially damaging to them in a way that it isn't for women. If you don't display fear, you tend to engender trust in others that you can handle the situation. If you do display fear, you tend to either be disregarded or treated protectively. Men are far more likely to fall into the 'disregarded and disposable' category while women tend to fall into the 'treated protectively' category. As a result, displaying fear is almost never advantageous for men while it can be for women. As to why these distinctions exist, there's some speculation that women evolved to be more timid and risk averse because their loss - especially if they're pregnant - is a greater loss than the loss of a man. If 90% of the men of your tribe are eaten by wildebeests and none of the women are, your tribe will recover in the next generation. If 90% of the women are so eaten, your tribe will suffer a demographic catastrophe.
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how does vaping vegtable glycerine, propylene glycol, and flavor concentrates (electronic cigarette juice) effect cilia trying to restore itself from cigarette smoke?
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We don't know for sure yet because vaping is so new there aren't any long term studies. There have been studies about fog machines, however, which use similar glycol or glycerine based fluids. _URL_0_ It's a long section, but tl;dr exposure to glycol fog has been associated with negative respiratory effects by a number of studies.While we don't know what the long term effects are, we do know that switching to vaping does allow the lungs to begin to heal and improves lung function almost as well as quitting cold turkey. However, nobody who vapes believes that vaping is "healthy". The correct term is "healthier" . If the FDA doesn't screw it totally up, vaping will probably emerge as the most effective cessation method, if not only for the fact that it's super easy to decrease the nicotine content gradually over time, while still vaping the same amount. Breathing just air > vaping > smoking.
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How does Moore's law work.
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They don't. It's not a law. He basically observed that: > the number of transistors that can be placed inexpensively on an integrated circuit doubles approximately every two years. *)* Not that it **has** to, but that it **seems** to do this when he made the statement, and is likely to continue to do so. He also said every 2 years, Intel revised this to 18 months. ***** Of course, there's the issue of beginning to reach the physical limits of our current methods, so we'll have to look into quantum computing but.. that's all the future, and not too relevant to the question. :)", 'They don't *have* to double. Moore's Law only describes a trend, it's not a law to determine what will happen in the future. If it rained everyday this week, and you say "It has rained everyday this week", it's a very different thing from saying "It has rained everyday this week, therefore it will rain every day next week". Moore's Law describes a trend, but it's not a universal physical law or anything of that sort.
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why will the sun burn something through a magnifying glass but if the sun hits eye glasses it wont burn your eyes?
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Because glasses don't so much magnify as distort the light going through them to focus it where the eye needs it. You can create a heat spot with some lenses but you have to aim them directly at the sun and angle them just right so generally it's not an issue.
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What is the difference between a muffler, a suppressor, and a silencer If there are only at all.
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a silencer is a made up thing movies use. a suppressor is a real thing that actually makes a gun sort of quieter but not even remotely silent or even quiet. A muffler is a car partA muffler goes on your car. Both the Silencer and the Suppressor are two terms for the same deviceA suppressor and a silencer are the same thing. However, "Suppressor" is the accurate term. "Silencer" is the more commonly used term for people who don't know a lot about guns. It is also inaccurate, as they do not silence the gunshot. A bullet fires when a firing pin strikes the primer of the casing. This causes a small explosion inside the chamber which forces the bullet out of the end of the barrel. A suppressor basically collects this expanding gas and diverts it into a a metal cylinder at the end of the barrel. The result is a smaller flash and quiet*er* gunshot. It does *not* make the gun silent and stealthy. The soft "*pfft*" sound you hear in movies and video games is pure Hollywood fiction. A suppressor can quiet a gunshot to hearing safe levels, but it will still be very loud. A muffler is a car part. It's basically a suppressor for your exhaust pipe.
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Why does Paper make such loud noises when I rip it?
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It is made up of a lot of strands with their own tension, when you rip paper you are breaking a lot of strands at once. Its like a rapid fire popping sound of that tension being released.
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Don't franchises suck the money out of local economies? Say a small town with 13 of the same coffee shop franchises. Also strangling local independent businesses?
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Franchises are owned by the owner of the franchise, not the corporation. It is a locally owned business, just not "independent" But its not really any different than an independent shop who buys their good to sell from outside the local area. Thats all a franchise is doing too, buying their good to sell from someone else. This might surprise you, but actually a lot of franchise locations like to have a connection with their local communities are make an effort to buy goods they can locally, as well as doing what they can to align their stores to the local area. In fact some companies that people can franchise, as a condition of their franchise, the company mandates that they do get local goods and such. Franchise isn't some dirty word. It's just someone that saw a business model with proven success and said "hey, I want to start a business, here's one that works, I'll do that". Nothing wrong there, risk is low, reward is solid, its hard to argue with it not being a good business decision to open franchise you think will succeed. Independent businesses are crazy risky and hard. Franchises have way less risk and are well known how to run.
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How long do you have to be dead before you're stopped being referred to as " the late"?. For example the late Margaret Thatcher sounds fine but the late Shakespear does not.
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That's an interesting observation. This seems like it's likely a vague thing with hazy boundaries that no firm definition will suffice for. With that said, though, I 'd say a good general rule might be something along the lines of "Margaret Thatcher was alive during the living memory of the vast majority of people who are currently alive", whereas Shakespeare was not. I say "vague and hazy" because obviously somewhere in between two extreme cases like Margaret Thatcher and Shakespeare, there is, say, Jimi Hendrix. Is it reasonable to refer to him as "the late Jimi Hendrix"? I think you'll find that different people have different opinions on that. And I think it's reasonable for them to have different opinions on it.
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How do animals have multiple births at a time and humans(most of the time) only have one
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It all revolves around our brain and development. Humans have adapted to give birth to highly developed offspring with big heads to house our complex brains. Brain development, big heads, and organs capable of supporting the brain take a lot of time to develop from a single cell . There are also a lot of resources needed for development. Humans get around these problems by devoting time and resources to a limited number of babies to insure their survival to maturity. It is not advantageous to waste resources during pregnancy or childhood on many offspring that will not survive. Other species have offspring that do not require as much resources or time from the parents. This allows them to produce offspring in large numbers more quickly because it does not cost as much and insures that at least some of the offspring will probably survive to maturity. There is no perfect system. Evolution has just produced different systems that work for different species.The number of live young typical in any species is tuned to give the best outcomes. Some species adopt the strategy of having a huge number of young but provide little or no care for them so that only a few survive. Mammals tend to provide more care so the numbers come down to how many young it's practical to care for. Human children require a huge amount of care to be successful so a very low number per pregnancy is preferred. Another factor relates to the size and maturity of the young. Human babies are limited by the size of the head that can fit through their mother's pelvis at birth. It seems there's selection for babies having the largest possible brains at birth. This is a problem for twins, triplets, etc., which result in more premature births with lower birth weight.
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why do we need coin currency? Why not set prices to a flat dollar amount?
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The fractal amounts are still meaningful in many transactions. For example, if gasoline could only be sold for $4/gallon or $5/gallon would make a huge difference to the vendor and the consumer alike. Also, some industries live off those fractions. Credit cards, for example, charge the vendor a small fraction of the charge. Each charge isn't that much, but when multiplied by the millions of transactions every day, they add up.
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What is the ethical justification(s) behind being pescetarian?
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I knew a girl once who was an outspoken PETA member and pescetarian. I think she just wanted to reap the moral superiority behind being a vegetarian, but liked fish too much. Not to make fun of Nonmeat-eaters. I know a very lovely Vegan women.Some people don't like eating meat due to the inhumane conditions in which they are raised. Since fish are not subject to the same methods, there's no problem.
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Why do my hands sometimes feel like they "fell asleep"?
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When you put enough pressure on a nerve or set of nerves they stop functioning correctly and your brain interprets that as pins and needles, pain or numbness. From the [National Institute of Neuroligacal disorderds and Storke]: > What is Pinched Nerve? > The term "pinched nerve" is a colloquial term and not a true medical term. It is used to describe one type of damage or injury to a nerve or set of nerves. The injury may result from compression, constriction, or stretching. Symptoms include numbness, "pins and needles" or burning sensations, and pain radiating outward from the injured area. One of the most common examples of a single compressed nerve is the feeling of having a foot or hand "fall asleep."Many people believe that it's because you cut off blood circulation to your extremity, by, say, falling asleep on your arm and waking up to find it numb. This is not correct. It's not a function of blood flow. It's a function of compression of the nerves in that extremity. When you put pressure on a nerve, that nerve doesn't conduct electrochemical signals the way it's supposed to. Put enough pressure on it for long enough, and it will take it a few minutes to recover. As the nerve is settling back into its normal state, it fires off spurious electrochemical signals that give you the "pins and needles" feeling
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Why can't everyone be nice to each other?
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I'd say for two main reasons. Humans love to break into tribes. With a clear divide between Us and Them. Typically that creates some sort of feeling of superiority or resentment. And also, treating someone like crap actually makes you feel good. It makes you feel powerful and important. It's why we like sarcasm and a good comeback. And those little micro-rewards in your brain create long term behavior patterns.
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How does diplomatic immunity work and why do we have it?
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There have been cases in which the other country will forfeit diplomatic immunity. There was a famous case in D.C. where a drunk Russian diplomat plowed down some people in Georgetown, and the Russians eventually waived his immunity and extradited him back to the U.S. But they didn't *have to.*
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How do hotel comparision websites earn money?
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Yes, they earn commissions. All of these online travel sites, whether for hotels or flights or whatever, are just travel agencies with a web-based storefront. Like traditional travel agencies, they earn a commission from the airline/hotel when they make a booking.
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How come when you step into the cold you always feel like you have to pee?
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So your pee has to stay at a constant temperature at above average body temp. So you're body needs to put extra effort to keeping your pee at the proper temperature. When you go outside the rest of your body feels colder because you are using more energy to preserve your urine temp. If you pee, your core temp will rise and is actually one of the things you should be aware of if you ever get stuck in a cold situation.
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Why doesn't the US or any other country use napalm/chemical warfare in modern day wars like in Vietnam?
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188 countries have signed the Chemical Weapons Convention which is an arms control agreement that outlaws the production, stockpiling and use of chemical weaponsNapalm got a lot of bad press during vietnam, so now the army uses [white phosphorus]
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Where do metals originate from?
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the coolest thing about all matter is that it comes from the stars - literally. Everything you see and everything you are made of is from an exploded star. Metals are fairly complex elements and so they come from only certain kinds of spent starsThey came from the same place that every other element on Earth heavier than hydrogen came from: They were fused from lighter elements in the earlier generations of stars that eventually went supernova and spread their material out into space only to have it coalesce into a new star and its planets . All of the carbon, oxygen, nitrogen, etc. on Earth was formed the same way.
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What happens to the sound on my headphones when they're not plugged in all the way?
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"Getting half a stereo feed" is exactly what you're hearing. Headphones are what we call Stereo, or Left/Right. Only one feed or side of that stereo is what we call Mono. On your headphone plug you'll see it is stereo because there are 3 conductors on it. The tip, the ring, and the sleeve. On a mono plug it would only have the tip and the sleeve. When you plug your headphones in, all 3 conductors make the connection and you hear the full stereo image. If you plug it in halfway, only 2 of the 3 connect and you only hear half the stereo image. Now, the reason it sounds weird is from the way modern day music is mixed. Modern day music is all about "how loud can we get this without sounding like crap?" To achieve this they separate the different "voices" or instruments between the stereo image to get certain elements louder than others. If you put all the sounds of the music at he same volume in both channels it will distort at the loud volumes we record music in. So if you separate them, you can get more volume without sounding like crap. Hope that answers your question.
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Why do other countries (outside of the US) have little or no commercial breaks on TV?
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As an example, I believe England has their stations technically run by the government, kind of like PBS here The US on the other hand leases out different bands to companies so they have to pay for their costsYou may want to be more specific as many countries have just as many commercials on TV as the US doesTurkey has 2 hour long shows with 1 hour advertisement. They usually take 7 to 10 minute breaks every 15 minutes.
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Why are dogs not intimidated when a human snarls and shows their teeth?
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Dogs are hard wired to recognize the body behavior of other dogs, not humans . Also, there is a lot of other body language going on besides just the noise and teeth baring at work that humans are physically incapable of reproducing. Edit: holy crap, make a quick half added paying and 24 hours later it explodes. 1. I did not mean to imply that dogs are incapable of reading human visual and auditory cues. What I meant was simple snarling and barring if teeth is likely to subtle fur the dog to recognize unless they have been trained to recognize it. And remember, not all training is deliberate. For those of you where just snarling and barring teeth work you probably trained then to recognize it at some point, maybe by using more recognizable cues the first few times such as aggressively approaching, hitting, etc. 2. Yes, other animals can recognize aggression in other animals. But the signs are always a lot more involved than just noise and facial expression. Physical posture, smell, movement all contribute to signaling aggression. Unless humans are truly being aggressive and subconsciously exhibiting these same cues, the dog is unlikely to recognize it. 3. Yes, dogs are the best animal at recognizing human cues. Maybe cats too but cats don't care where dogs are hard wired to please humans. But they still have to be trained to understand what we mean. Unless trained they have no idea what we mean when we try to mimic their behavior.
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what is my body doing in the "Aaaah, AAAAAAH-" moment of a sneeze? Why does it vary in length?
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When you start to sneeze, it's because of some sort of irritation in your nose to release histamines. When histamines reach the nerve cells in your nose, it tells the brain to start what I'll call the Sneeze Sequence. The "Ah" sound you make is due to your body reflexively taking a large breath. During this time, the muscles in your throat and nose expand, creating an opening that allows large amounts of air to pass through. Then, your chest muscles rapidly contract, forcing the air out of your lungs and through your nose. The variation in length is based on personal anatomy and how your brain handles the Sneeze Sequence. It's different from person to personYour body is preparing the expulsion of air, to clear the airways, by forcing you to breathe in, the "ah" part. The duration varies due to the volume of air currently in your lungs, and your own biology. Everyone reacts differently.
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When a song gets "leaked", where does it come from?
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When a band is recording a song or album, there are many people involved from the time they start recording until the media is sent out for sale. Any one of the people who are involved in that process can get a copy of the song or album and leak it. So, once the music is recorded and mixed, copies of that music are sent to various groups. Anyone that touches the media has a chance to make a copy. Some artist actually put some sort of unique signature on the different files that they provide to different parts of the process. This way, if they happen to find a version of their song released on the Internet, they can much more easily track down who stole the song and released it.
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Why is it that the brain remembers seemingly unimportant events and encounters but not information that can considered more useful?
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I think it is the wrong question, because the brain *does* remember useful information. Just not every time. So the question is rather: why is the brain not *perfect* at distinguishing out what to store safely? If you accept "why expect perfection from humans?" as an ELI5 answer, then good. Otherwise my, this could be a tough one.
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What causes small droplets of saliva to be launched out of your mouth sometimes when you open it.
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I think you are refering to gleeking. In general, gleeking occurs when an accumulation of saliva in the submandibular gland is propelled out in a stream when the gland is compressed by the tongue. The stream of saliva is released in the general direction of the front of the mouth. If the mouth is open the jet may project several feet. Some people can do this on command by pushing/ramming their tongue against the the back part of their front upper teeth. I can lol lightly biting my tongue in different areas to stimulate salivation helps do it repeatly.
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Why is there a ringing in your ears in total silence?
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Assuming there isn't anything in your parents house that actually emits that sound , then the sound is "imagined" by your brain, it's not actually there. It all comes down to your brain not receiving a signal for certain frequencies. This can have many causes , most common probably being damaged hair cells . Your brain expects a signal, but there is none or it's too low, so it basically cranks up the sensitivity. Imagine trying to get a radio signal, you can't receiving anything so you increase the amplitude, but since there is no signal to begin with you just hear louder static noise. It's always there, if you're in the city it just gets drowned out by the background noise so you don't noticeCould be that you have [tinnitus]. > Tinnitus\xa0is the hearing of\xa0sound\xa0when no external sound is present. While often described as a ringing, it may also sound like a clicking, hiss or roaring. Rarely, unclear voices or music are heard. The sound may be soft or loud, low\xa0pitched\xa0or high pitched and appear to be coming from one\xa0ear\xa0or both. Most of the time, it comes on gradually. In some people, the sound causes depression or anxiety and can interfere with concentration. Browse around /r/tinnitus a bit to see if anything there seems familiar.
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How do dogs decide where to use the restroom?
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Dogs may circle their chosen bathroom site as a way to stomp down grass and weeds in order to have a place to poop. Originally, wild dog ancestors may have lived in areas with long or tall vegetation and they developed this instinctual behavior to maintain their hygiene while defecating. Another explanation could be that since dogs are vulnerable to attack by predators or other dogs while squatting, they may circle in order to be able to spot any potential threats and make sure their "toilet" is safe and secure before going to the bathroom. If they find a threat, such as a predator lurking nearby, they may leave to a safer location before going to the bathroom. Most animals use excretory products as chemical signaling. They "mark" their territory this way. Dogs sniff to find out who else has marked the territory, before leaving. Although since it's your backyard, this probably isn't the case here if it's fenced in.
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Why does it feel so much better to get a massage than when we rub our own shoulders or feet, etc?
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Because you are not relaxed when you are working on your body and focusing. When someone else does it for you you can relax and physically and mentally shut down.
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Why do Catholics pray to Mary and the Saints?
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Catholics believe that the saints and Mary are very close to Jesus and God. They don't pay directly to saints and Mary, but rather they pray that they intercede for them. Meaning that the saints pray to God on their behalf, and since they are so close to God to put in a good word
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How come Google can search the entirety of the internet instantly but when I search my C: drive through the Windows Start Menu it takes forever?
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It's because of indexes. When I want to find something in a textbook, I go to the index first. That helps me find the right page. If there was no index, I'd have to read every page until I found the right one. That could take a long time. Your C: drive probably doesn't have an index. It is possible to create an index, but it's quite a basic one. Google has lots of extremely advanced indexes to help it find the information quickly.
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How do fans work if all they do is warm the air?
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While, technically, heat is the result of molecules moving faster, in practice you need to make air move hundreds of miles per hour for it to become measurably warmer. The little 10mph breeze from a fan is basically an immeasurable increase in the energy of that air. Our bodies are hot so the air around us heats up. A fan blows that hot air away so we radiate more heat into the outside air. It also helps our sweat evaporate a bit faster, cooling us down further. When this naturally occurs outside, we call it "wind chill".
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Why Gravity/General Relativity and Quantum Mechanics don't fit togeather
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There's something physicists do in quantum field theory called renormalization. Basically, you often end up with values that are infinity, but you can "renormalize" them by subtracting another infinity of the same "size." This is mathematically and logically weird, but it turns out to work. With the electromagnetic, strong, and weak forces, you can use renormalization. With gravity, though, you can't. There are lots of rules from general relativity that a theory of gravity has to follow, and those rules make it impossible to renormalize the equations. Thus, you end up with values that are infinity, negative infinity, whatever. That's not good, because it's clearly not the correct answer. One of the proposed solutions to the problem is string theory, which you can look into by using the ELI5 search function . Basically, when you start trying to turn quantum mechanics into a relativistic theory, you get stuck at a "fork in the road." You can "demote position," which is how you go down the quantum field theory road, or you can "promote time," which leads to string theory. Quantum field theory is easier to work with for a lot of reasons, so physics spent a lot of time going down that road hoping things would work. It seems not to, though, so now a lot of theoretical physicists are checking out the string theory side.
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Why is "they are" correct grammatically, while "everyone are" is incorrect, when they are both used as singular pronouns?
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Think of 'everyone' as 'each and every one'. 'One is', singular. 'They' is used when there is a plurality of people *or* when there are plural options for addressing someone and you don't know which to use. 'They are', plural."They are" is plural. It's the fallback for when I don't know if a person is a he or a she, so I use they, but I'm still talking in a plural form. "Every*one* is" is singular.
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the consequences of not bailing out the big banks and companies
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When a company of that size goes under it's not isolated. You have to understand that our money is built on debt and the expectation that that debt will mostly get paid. Generally what happened is you own stock in Company A. A own stock or debt in B and B in c and c in d. Now D fails. This brings down c to a as well. So now you have lost a lot of value. So you don't buy that TV. Because of that company Sony loses money. Which then company t goes down in value. Also some stock or debt you own. Now you've lost more money and aren't going to fix the broken pipe. Everyone starts hoarding their $$$ because everyone knows tomorrow is going to be worse than today. Banks are now not loaning any fiat because they can't be sure they'll be repaid and small company Z cannot get a loan to cover operating expenses until it gets paid from company T and needs to lay off workers. We'll now you've lost your job so you aren't buying a whole gallon of milk. Small business T and Z is also foreclosed on. Selling off its assets. But of course no one has money so the assets are sold off at 90% of their original value. The bank now just lost a lot of money. This isn't exactly what happened but is representative of what we were facing. Our system is based on tomorrow being better than today. When that doesn't happen then the game is over.
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Why are most company head quarters in California?
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California is the most populous state and it's been a major tech hub for several decades now. But there are plenty of major companies that aren't headquartered there- financial firms are more likely to be based out of New York or Chicago, defense companies are more likely to be based out of Washington DC or nearby in Maryland and Virginia. There's lots of advanced tech research like robotics and langauge processing based out of Boston. Washington and Texas also have a large number of tech companies, including Amazon and Microsoft in the Seattle area and Dell just outside of Austin.
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Why American toilets don't have a half-flush feature?
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It hasn't really caught on as the standard yet in North America because – compared to Australia – the United States and Canada have very large sources of fresh water . North America also tends to have a lot more precipitation, so rainwater is helping to replenish fresh water sources all the time. Basically there is no danger of North America running out of fresh water sources. There are particular areas in the United States that are prone to droughts and where water restrictions are sometimes put in place. In general though, there isn't the same concern for "wasting water" in North America because, for the most of the continent, the fresh water supply is basically unlimited and it wouldn't be possible to use up even if we were trying to. Australia is in a much worse off position because access to fresh water is very limited and, although seawater is in abundance, it's extremely expensive to desalinate seawater. Therefore, wasting fresh tap/toilet water becomes a major problem in Australia since it potentially impacts the amount of fresh water available that other people have to rely on for drinking, cooking food, and hygiene. There is an effort to introduce half-flush toilets in North America though, and it is possible to buy them in stores. They just haven't yet taken over as the default standard in most bathrooms yet.
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Why does saliva sometimes spray out of your mouth like a shower when you yawn?
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It's caused by accidently putting pressure on the saliva gland under your tongue. The slang term for this is 'Gleeking' .Ok I feel like a freak now, I do this all the time. You can control it by kind of folding your tongue back under you front teeth, so the underside i pointing out, then press your jaws down on each other, putting pressure on the tongue. To reset just close your mouth for a second and do it again, fun for all the family.If you know that you do this, can you guys please not yawn or suddenly speak while your head is pointed at other people please? Start your sentences while facing your head a few degrees away from me and then turn to talk to me. It's so awkward to be spat on I never know if I should acknowledge it or just pretend that I didn't notice. But then when you reveal with your reaction that you noticed it then that just makes it doubly awkward.
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Why does ice sink in warm grease but float in cold?
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Like most things, grease expands as it heats up. As a result, cold grease is denser than warm grease, so I've can float in it.
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How the street names of New York are organised e.g. 30 & 5th.
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The roads are set up like a grid. There will be a Central St/Ave tha is where the numbering starts. One direction will 1st Ave North, 2nd Ave North, 3rd Ave north, etc. The other will be 1st Ave South, 2nd Ave South, 3rd Ave South. Their cross roads will often be be the opposite 1st St, 2nd St, 3rd St. The "St" will often start in an area close to the edge of town so that only one direction will have the North/South aditive to avoid confusion.Streets run east and west in Manhattan and Avenues run north and south. Since manhattan is kind of long and skinny, you have more streets than avenues. Avenues run from 1 to 11 and streets run from 1st st. to 110th st. after that your in Harlem not Manhattan, even though you're still on the island of Manhattan.
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Why does cannibalism have negative side effects?
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Any disease that the person who died has is obviously capable of infecting other humans. And societies tend to look down on eating their own, because it would be seen as encouraging murder. But otherwise, yes, meat is meat. It is said to taste a lot like porkCannibalism is a great way to transmit protein based diseases like kuru, depending on the part you eatThere are two negative side effects of cannibalism that we see from history: 1. Diseases such as kuru. New Guinea cannibals were prone to this disease which is very similar to "mad cow disease", drives you mad and then kills you. Is a nasty way to die. 2. Fear and loathing from other human societies. Since many human societies seem to have a strong taboo against cannibalism, they tend to sub-humanise those who practice it, and work hard to wipe them out. For example, the Spanish Conquistadors in Mexico felt that the Aztec practices of human sacrifice and cannibalism were so horrific and evil that almost any measures were justified in trying to extinguish them. They succeededEating the brain led to degenerative disease in the Fore people of Papua New Guinea . The meat would be fine, but I imagine you would have to take precautions like you would with any other meat - no visible cysts/parasites etc. Also, eating the liver of certain animals can kill you due to the high Vitamin A content. Indigenous groups in the Arctic avoid the liver of polar bears because of this.
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What is the difference between shaving using a trimming machine , a razor or waxing besides the physical method and why is one preferred over the other
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A trimmer leaves the hair partially there and is merely cutting it down to a certain length. You use this when you want to keep your beard but groom it, and trimmers are often used when doing normal haircuts for the areas that are going to be relatively short. A razor cuts much closer, shaving off almost all of the exposed hair and leaving skin that looks smooth. Waxing coats the skin and solidifies, binding the wax to the exposed hair. Placing a sticky strip on the wax and quickly removing it then rips the hair out of the follicle down to the root, resulting in a lack of hair until it can grow from the root again, which should last 1-6 weeks or so depending on the person.
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How do aquired tastes work?
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It doesn't smell any different to you as it does to me. You have created associations in your brain between the smell, the taste, and the effect. You enjoy the effect, so you start to enjoy the smell because you anticipate the result. It still has the same smell though chemically to your smell receptors in your nose. You can use this to create small Pavlov situations. You may hate broccoli on its own. But if you start to put broccoli in things you enjoy to eat, you slowly create the same associations. Over time with enough positive associations, broccoli on its own becomes good to you, because you think about everything else as well.I’m no expert but if I had to think about it I would say it’s just trying it. With the weed example some people think it’s horrid but if they try it their opinion may change. Same goes for music. Genres like deathcore and metalcore aren’t for someone who likes country or pop. It’s a matter is trying and then going from them.
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why does milk taste so good after eating something with syrup or peanut butter?
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**Likes disolve likes. Polar substances like water disolve polar substances like sugar. Non-polars like oil, fat, and gasoline dissolve non-polars. We've all seen this, oil doesn't mix with water. Chocolate and peanut butter have fat which don't disolve well or at all in water, but do in milk because milk has fat.**
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Why do we get blisters when wearing new shoes for the first time?
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The average foot is covered with fairly soft and scrapeable skin. That skin wears away when it's rubbed or tugged against something over and over again. If the constant pulling action is along the surface of the skin and it's in short quick jerks, it can actually separate the top layer of your skin from the bottom. Fluid fills the middle and you get a blister. So take that foot and jam it into a shoe that doesn't fit properly and you create a number of pinch points. As you walk and your weight shifts that foot around a little in your shoe over and over again in the same way, the conditions near the shoe's pinch-points can be perfect for this tugging action to occur, resulting in blisters. If the shoe is a "near fit" and you continue to walk in it over time, it softens due to the repeated stretching, some of the seams wear down a tiny bit from friction, and its leather or other content molds and stretches to accommodate your foot better. This reduces the pulling action because it's no longer pressing against your skin in the same way, so you don't get the blisters any moreBecause you are less than amazing at buying shoes from the get go. This issue arrives from buying cheep shoes and trying to cram a foot that is the wrong shape for the shoe. LPT, put on super thick socks and run a hair drier over the shoe. It will help shape it quicker if there is a shoe you must absolutely have
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The Difference between a Mechanic, Technician, Engineer, etc. I hear the terms used (seemingly) interchangeably.
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Mechanic generally only means someone working on engines. Technicians are doing practical work with something at least vaguely technical. You could call a mechanic an auto-mobile technician or something if you want to. An engineer generally mean a university-trained professional that designs new systems; they often leave the actual act of installing things to technicians. An engineer designs a plane, a technician/mechanic actually puts it together and makes sure it's going according to plan.
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Can electric appliances cause WIFI disturbance?
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Motors with brushes have some arcing associated with them. The arcing emits a very wide range of frequencies which can interfere with any consumer radio system. _URL_0_WiFi is an electric signal using a wavelength. I doubt the vacuum motors induced magnetic field would be strong enough to alter the WiFi signal. But there is a form of disturbance on the power side of router caused by motors and transformers called magnetic resonance. Induced voltage caused by AC motors can distort the AC wave form. Some engineers and electricians call this “dirty power”. This causes extreme problems in electronic systems like routers. There are RC filters built into most equipment but sometimes they are not stout enough to deal with larger distortions. The best solution is to invest in a really good surge suppressor. They have robust RC filters built in and should clear the problem. The other method involves knowing which phase each receptacle is on and gets a little complicated.Depends on the appliance. As the others have mentioned, motors can cause some signal interference, and this is typically reduced by making the enclosure of the appliance out of metal, and grounding it, in order to form a [faraday cage]. Modern vacuum cleaners are made of plastics, so that's a problem. On the other hand, something like a clothes washing or drying machine, with its metal enclosure, will likely cause much less EM interference, despite also having motors inside.
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Why do we chill when we are actually burning with fever?
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There's a part of your brain that controls your temperature called the hypothalamus. When you get a fever, your immune system makes your hypothalamus change your desired temperature higher. Your body basically wants to get warmer, so it makes you feel cold. When you feel cold, you try to get warmer yourself and you shiver to move your body to create warmth. Your body forces you to feel cold because it wants you to get warm. If you felt hot, you would try and cool yourself down, which is the opposite of what your body is trying to do.
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Why do televisions often cut the end off of recorded programs, even if space is available?
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They often have a schedule for advertisers and later programming, and the program was "fudged" in that time slot. Sometimes programs, especially live broadcasts, go over or under time by a few minutes, but shows later in the day have to be on at a certain time. Since everything is set to run in the same time intervals, the gap moves on down the line thriving the day so they often prefer to cut some time from somewhere else to make it work.
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What does "meta" actually mean?
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Meta means "viewing things at the next higher conceptual level". For example, an analysis might study the effectiveness of a particular drug. A meta-analysis studies multiple analyses. Meta can **sometimes** result in self-reference, like a TV show making a joke about being a TV show. But saying meta is the same as self-reference completely misunderstands what is actually means"Meta" means "self-referential" or "referring to the thing itself". One common usage in neuroscience is the concept of meta-cognition, or "thinking about the process of thinking". In the Internet, it's commonly used to discuss self-referential humor, and leads to things like: "I'm so meta, even this acronym", where, if you convert that sentence into an acronym, it spells "is meta".
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Student debt is making it harder for millennials to buy houses in stead of renting. What effect will this have on the economy?
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Student debt is not just dragging down the housing market, it's dragging down the entire economy. Reducing the discretionary spending power of the currently largest demographic block in the US is obviously detrimental to the entire economy. Part of why the US's growth rate in the past 10 years has been less than stellar is partially because student debt has curtailed millenial spending. Reducing discretionary spending reduces functional demand, reduces economic growth. If we really want to free up the economy, we must address the student debt problem. Specifically, for housing, this will reduce appreciation and likely harm the retirements of boomers who were counting on the profits from real estate appreciation. It will also slow down family creation and marriage rates, both of which should slow the economy as well.
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Why do we need car dealerships?
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Same reason we need any store, some people like to try things out before they buy itAs I recall, the "car dealership" model was put in place to prevent Ford from having a monopoly on the car selling industry. A new car manufacturer wouldn't have to compete with the entirety of Ford, it would have to compete with a number of local dealerships who are also competing among eachotherDealerships also act as a distributor of genuine parts and an authorized repair facility. In theory dealership mechanics are experts on the specific systems of a particular brand of carIt is much easier to do business with a local owner than try and do business with a disinterested party thousands of miles away.
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How is it possibly true that "the Girl Scout Cookie Program is the largest girl-led business in the United States" - is it really led by girls?
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I believe that almost all the upper level management of the Girls Scouts is also female.Their CEO is currently Anna Maria Chávez, and if you look at their [list of past leaders], it's pretty much entirely females. So yes, it's a very large business that's led almost entirely by women. I'd say their material checks out.
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Where have all the college-student jobs gone?
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Well, for starters, in 1979 you could pay for an entire semester of college by working for two weeks at minimum wage. In 1993, you could pay for a week of school with 20 hours of minimum wage work a week. Now, you have to work 48 hours a week of minimum wage to pay for school. So, it makes more sense to take out a student loan and actually have time to go to school than to work while going to school. [Source]
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Why is it always so cold in the hospital?
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Bacteria and viruses don't survive as long on cold surfaces. Making it a bit chilly saves lives from infection.Hospitals and other healthcare facilities have high air change rates, sometimes up to 25 air changes per hour for an operating room. So every hour the entire volume of air in that space is being supplied and exhausted almost every 2 minutes. Paired with some beefy filters, bacteria and any other airborne particulates are exhausted out of the room before they can settle on anything. Since generally, air is supplied to a space around 55 degrees when in cooling mode, a facility with high air change rates, such as a hospital or lab, tend to be cooler.
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home come drinking salt water makes you vomit, but having something like chicken broth doesn’t? Even though it has water and salt in it
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Pretty sure there's way more salt proportionally in ocean water than even the saltiest chicken broth.Salt water? 🤔 Like drinking water from the ocean?
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Why does the hair on your head need to be cut continuously but the hair on the rest of your body knows when to stop?
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All hair have a certain lifespan, your eyebrow and eyelashes can only grow for a month or two before they die and fall off. Your hair on the other hand can grow for about 7 years The hair on your head also has a terminate length. It is just much longer than body hairIf you let your head hair grow normally, it would stop at a certain point too.
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Why do I crave something specific when I'm hungry and some times I don't know what I want? What is happening in my body?
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Sometimes your body will be lacking so kind of mineral/nutrient, so it will direct you towards foods containing that nutrient. It could also just be dependent on sensory cues.
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Why do most rappers say "uh, yeah" before a song?
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It's just a way for rappers to find their rhythm and get into the song. It's the equivalent of bobbing your head to the beat or something.
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Why do bubbles have that strange rainbow kinda color?
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Very thin films take on a sharp color. This is due to light reflecting off of both surfaces of the film and interfering with itself. This happens with a bubble, but the film is not uniform in thickness. So instead of getting one very distinct color, [you get rainbow patterns].
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What are the current Problems with nuclear Fusion?
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You are creating something as hot as a star. No physical material we have is strong enough to withstand that kind of heat and pressure. Any metals, ceramics, even carbon nanotubes would melt and rupture instantly. So the reaction is contained by floating it inside of a magnetic field so it doesn't actually touch anything. This field has to be very strong to contain the energy being created, and so it takes a lot of energy to keep the field up. Currently we can create fusion reactions, but we always end up putting more energy into them than we get out of them. We either need to find a way to generate more energy in the reaction without needing additional energy to contain it, or we need to increase the efficiency of the magnetic torus that contains the reaction so it doesn't take so much energy to maintain. This is why cold fusion is so sought after, because without all of the heat then you don't need high energy toruses to contain the reaction.
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How are denial of service attacks still possible?
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Same reason McDonalds can't do anything about one guy coming in an ordering 30 large fries and holding up the entire store for a half hour. That's basically what a DDoS attack is. There are counter measures that these companies take, but ultimately there is little they can do that would not also negatively effect their business. Best solution for Lizard Squad is to get the FBI involved and have the lot of them arrested. A couple years in prison with "Horse Cock" Charlie should straighten them out.
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Why are simple antibiotics not available without a prescription?
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Because antibiotic resistance is a huge problem. People overuse antibiotics for things that sometimes don't even need them, like the flu which is a virus and not bacterial. If the general public were able to purchase antibiotics off the bat then resistance would go up massively. Plus, there are so many different types of antibiotics that the general public wouldn't even know which ones treat what illnesses. The ABX for UTIs tend to be different than that of strep, or staph, or STIs etc Source: I'm a medical professional
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This difference between running inside and running outside
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ELi5 isn't really for questions about personal health so this has been removed. If serious ask a doctor.
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What is the difference between emotional infidelity and a close friendship?
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There is no big book of relationship regulations. Discuss relationship expectations with your partner. But personally if my partner expected me not to be close with my friends, I would not accept that.
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Why don't laptops have a slot to clean fan dirt?
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The more user-servicable you make a piece of electronics, the bulkier and less reliable it will be. People generally make their purchasing decision based on aesthetics or specs and not on the ease of maintenance. This is the same reason that iPhones don't have removable batteries.
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- how can you get stretch marks on your bum from sitting down too much?
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Your can't. You get stretch marks from rapid weight gain or growth. So if you put on a lot of weight in your hips and butt you can get stretch marks there. Something you can get from sitting down too much are pressure sores commonly called bed sores, or hemorrhoids.
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This morning I read that the universe is expanding at a rate of a billion miles an hour in every direction. Does this include the space within in my own body?
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Imagine blowing up a balloon. The balloon gets bigger, and two points far apart on the balloon get further apart very quickly. But two point which are close together move further apart only very slightly as the balloon inflates. The universe is a bit like that. So the space which your body exists in *is* expanding, but only very slowly, because it's such a small piece of space. To get the massive rates of expansion you've read about, you need to look at the rate at which two points many many light years apart are growing apart from each other. Fortunately, the forces that hold atoms and molecules together can easily overcome this small rate of expansion, and hold us, our planet and everything else we depend on together.
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When a tennis player challenges an in-out call, how is the CGI clip generated to make the right call?
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Cameras track the ball's movement with a technology called "computer vision". This is a powerful tool that is used to identify rejects in an assembly line, and what self-driving cars use to navigate, for example.
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when I sleep in my bed and my hand touches the concrete wall, it feels really cold but when I touch my wood bedframe it's warm.
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Hotness/coldness isn't a measure of the temperature of the object. It's a measure of how fast the heat enters or leaves your hand. A metal bar feels colder than a wooden one on winter's night because metal is a better conductor of heat. It literally sucks the heat out of your hand faster than wood. Concrete isn't as good as metal, but it's better than wood.
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Why exercise speeding up your heart rate is good, but drinking caffeine to speed it up is bad?
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Ok, best guess here, only because no one else has bothered to give a decent answer, would be that exercising to keep your heart rate up is only a benchmark for how you should feel to know you're doing it right. Having an increased heart rate alone is not the point. Obviously when you're exercising, it effects a lot more than your heart; your lungs, your muscles, how many calories you burn, etc Edit: Forgot to mention that even hardened athletes who are used to doing really tough physical exercises don't just start and stop cold turkey. They do stretches and warm ups prior to doing their full exercise and they do slower/weaker exercises to cool down after the main workout. Forcing your heart to beat rapidly through the use of a drug offers none of the warm up or cool down periods, so it's extra stressful on your heart, compared to exercise, with none of the other bodily benefits of exercising.
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How do Blood Thinners (Rat Poison) work? What makes the blood "thin"?
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Your blood contains things called platelets - these are basically a type of cell whose job it is to plug any holes that might form in your bloodstream. And normally, these holes and tiny tears happen *all the time*, but you never notice them because your platelets plug said holes and prevent any leakage. Blood thinners, both as a rat poison but also used for medical treatments , work by preventing these clots from forming. This can be done through different pathways, such as interrupting the chemical signatures the body uses to conduct the clotting process or by accelerating the processes that the body uses to break down bloodclots. Rat poisons operate through the first method - by interrupting the clot-forming pathways. Also included in rat poison are other chemicals that cause the blood vessels to be more 'leaky', speeding up the process of internal bleeding.Your body produces a large number of "clotting factors" to assist in helping your blood coagulate. This is really useful in terms of minor cuts and trauma that need fast clotting and happens very regularly. Rat poison usually contains warfarin, a chemical that stops vitamin K from forming these clotting factors. Blocking these clotting factors leads the blood being unable to coagulate and causes internal bleeding in the rat. Only a very small amount is needed to cause serious bleeding. This chemical is also used as a drug to prevent strokes, DVT and other conditions caused by blood clots.
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When a woman gives birth how long does it take for her stomach area to go down?
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It's different for each woman and it just depends on her body type, whether she delivered vaginally or by cesarean, and her activity levels before and after pregnancy. I mean, she will immediately not look pregnant anymore once the baby and placenta are out, but she won't be back to her pre-baby size for a while, and some women never do go back to that size. A woman's abdominal muscles can weaken from being stretched out over a huge belly and until she strengthens them again, they will sag outward after she gives birth.
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Why can't we just throw satellites or sensors into a black hole to see what happens?
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The nearest black hole is 1600 light years away, for a start. Even if we have a black hole at easy reach the definition of a black hole is that it is so massive that its escape velocity is faster than the speed of light. Information can't move faster than light, so if we sent a satellite into a black hole it and all of its data would be lost as soon as it crossed the event horizon.
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From a cancer-risk point of view, is 10 minutes in the sun each day for 12 days equivalent to 2 hours in the sun during one day?
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If you burn, it's definitely not equivalent. When you get burnt, your skin is showing signs that cells are actually dying. Your body contains mechanisms to deal with the DNA damaged caused by UV radiation, but when these mechanisms become overwhelmed, your cells need to abort and kill themselves to prevent skin cancer. It might be more equivalent if you didn't develop a burn in the long-exposure scenario. Bad sunburns in childhood are particularly associated with skin cancer risk, but so is overall sun exposure.No, you are not over exposing your skin to uv radiation in 10 minutes like you could be in a 2 hour period.
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Why has Africa generally been unable to develop like the rest of the modern world?
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It's not that Africa hasn't been able to develop, it's been actively undermined. Nearly all of the continent was under colonial administration until the end of World War II. It's spent hundreds of years having its resources siphoned away and having its political systems eroded. Once independence finally came, it was granted along mostly arbitrary lines. There's no national cohesion because the borders of states were basically drawn at random, not along any sort of national lines . Really, it's going to be generations just to get people in a lot of these countries to stop hating each other long enough to get basic stability. After about 400 years of being shot in the foot, I seriously doubt that the continent as a whole will *ever* catch up to Europe or North America. Some specific countries will do well, but most are deeply and systemically broken.
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How do those penny auction websites work?
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The price of the items is dirt cheap. But what they fail to mention is that you have to pay for bids and the auctions end times extend after every bid. So while you may have purchased that new laptop for $10, you spent $500 in bids, just like all the losers of the auction also spend hundreds in bids.tl;dr: The _winner_ pays very little, but all the _losers_ pay a little bit too. It's effectively the same way a lottery works: You can pay 5$ and walk away with a 1,000,000$ win, but everyone knows that over 200,000 other people had to lose last time for them to afford that payout.
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how do scientist discover new things about the universe?
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They do it with the scientific method: 1) Conjecture that something "could" be possible . 2) Create an experiment that will test your hypothesis in such a way as to be sure you are actually measuring what you think you are measuring. 3) Use the results of your experiment to classify your initial hypothesis as valid or invalid. 4) Refine your original hypothesis and start the process again. From an astronomy standpoint, it would look like this: 1) Conjecture that there are Earth-like planets out there. 2) Build an "experiment" that uses telescope data to look for exo-planets that have the approximate correct mass, are in the correct orbit and have spectrographic readings indicating the right atmosphere. Nearly all of the data collected comes from automated radio telescopes and occasional optical scopes. More statistical analysis of numbers than peering through a tube. 3) See if you can find any previously unidentified planets that match your criteria. 4) If not, perhaps you need to relax your requirements or build better equipment. Wash, rinse, repeat.
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