id int64 0 18.9k | biography stringlengths 151 1.51k | qa listlengths 1 25 |
|---|---|---|
4,991 | Islam arrived 1,400 years ago in Zhejiang. Today Islam is practiced by a small number of people including virtually all the Hui Chinese living in Zhejiang. Another religion present in the province is She shamanism (practiced by She ethnic minority). | [
{
"answer": "1,400 years",
"question": "How long ago did Islam arrive in Zhejiang?"
},
{
"answer": "Islam",
"question": "What religion do the Hui Chinese living in Zhejiang practice?"
},
{
"answer": "virtually all",
"question": "How many of the Hui Chinese living in Zhejiang practice... |
4,992 | Zhejiang is mountainous and has therefore fostered the development of many distinct local cultures. Linguistically speaking, Zhejiang is extremely diverse. Most inhabitants of Zhejiang speak Wu, but the Wu dialects are very diverse, especially in the south, where one valley may speak a dialect completely unintelligible... | [
{
"answer": "extremely",
"question": "How diverse is Zhejiang, linguistically speaking?"
},
{
"answer": "Wu",
"question": "What do most inhabitants of Zhejiang speak?"
},
{
"answer": "with Anhui",
"question": "Mandarin and Huizhou dialects are spoken on the border where?"
},
{
... |
4,993 | Throughout history there have been a series of lingua francas in the area to allow for better communication. The dialects spoken in Hangzhou, Shaoxing, and Ningbo have taken on this role historically. Since the founding of the People's Republic of China in 1949, Mandarin, which is not mutually intelligible with any of ... | [
{
"answer": "1949",
"question": "When was the People's Republic of China founded?"
},
{
"answer": "Mandarin",
"question": "What has been promoted as the standard language of communication throughout China since 1949?"
},
{
"answer": "1978",
"question": "A majority of the population e... |
4,994 | Zhejiang is the home of Yueju (越劇), one of the most prominent forms of Chinese opera. Yueju originated in Shengzhou and is traditionally performed by actresses only, in both male and female roles. Other important opera traditions include Yongju (of Ningbo), Shaoju (of Shaoxing), Ouju (of Wenzhou), Wuju (of Jinhua), Tai... | [
{
"answer": "Yueju",
"question": "What is one of the most prominent forms of Chinese opera?"
},
{
"answer": "Shengzhou",
"question": "Where did Yueju originate?"
},
{
"answer": "actresses only",
"question": "Who is Yueju traditionally performed by?"
},
{
"answer": "actresses"... |
4,995 | Longjing tea (also called dragon well tea), originating in Hangzhou, is one of the most prestigious, if not the most prestigious Chinese tea. Hangzhou is also renowned for its silk umbrellas and hand fans. Zhejiang cuisine (itself subdivided into many traditions, including Hangzhou cuisine) is one of the eight great tr... | [
{
"answer": "dragon well tea",
"question": "What is Longjing tea also called?"
},
{
"answer": "Hangzhou",
"question": "Where does Longjing tea originate from?"
},
{
"answer": "silk",
"question": "What type of umbrellas is Hangzhou known for?"
},
{
"answer": "hand",
"quest... |
4,996 | Since ancient times, north Zhejiang and neighbouring south Jiangsu have been famed for their prosperity and opulence[citation needed], and simply inserting north Zhejiang place names (Hangzhou, Jiaxing, etc.) into poetry gave an effect of dreaminess, a practice followed by many noted poets. In particular, the fame of H... | [
{
"answer": "Jiangsu",
"question": "What neighbours north Zhejiang to the south?"
},
{
"answer": "Zhejiang",
"question": "What neighbours south Jiangsu to the north?"
},
{
"answer": "prosperity",
"question": "North Zhejiang and south Jiangsu are famed for their opulence and what else... |
4,997 | The Ministry of Defence (MoD) is the British government department responsible for implementing the defence policy set by Her Majesty's Government, and is the headquarters of the British Armed Forces. | [
{
"answer": "British",
"question": "Which government's Ministry of Defence is mentioned here?"
},
{
"answer": "Ministry of Defence",
"question": "What does MoD stand for?"
},
{
"answer": "Her Majesty's Government",
"question": "Who sets the defence policy in Great Britain?"
},
{
... |
4,998 | The MoD states that its principal objectives are to defend the United Kingdom of Great Britain and Northern Ireland and its interests and to strengthen international peace and stability. With the collapse of the Soviet Union and the end of the Cold War, the MoD does not foresee any short-term conventional military thre... | [
{
"answer": "international peace and stability",
"question": "What does the MoD wish to strengthen?"
},
{
"answer": "Great Britain and Northern Ireland",
"question": "The UK consists of what two areas?"
},
{
"answer": "United Kingdom of Great Britain and Northern Ireland",
"question"... |
4,999 | During the 1920s and 1930s, British civil servants and politicians, looking back at the performance of the state during World War I, concluded that there was a need for greater co-ordination between the three Services that made up the armed forces of the United Kingdom—the British Army, the Royal Navy, and the Royal Ai... | [
{
"answer": "the British Army, the Royal Navy, and the Royal Air Force",
"question": "What three services make up the armed forces of the UK?"
},
{
"answer": "The formation of a united ministry of defence",
"question": "What did David Lloyd George's coalition government reject in 1921?"
},
{... |
5,000 | Winston Churchill, on forming his government in 1940, created the office of Minister of Defence to exercise ministerial control over the Chiefs of Staff Committee and to co-ordinate defence matters. The post was held by the Prime Minister of the day until Clement Attlee's government introduced the Ministry of Defence A... | [
{
"answer": "Winston Churchill",
"question": "Who created the office of Minister of Defence?"
},
{
"answer": "1946",
"question": "When was the Ministry of Defence Act introduced?"
},
{
"answer": "1940",
"question": "When did Winstron Churchill form his government?"
},
{
"answ... |
5,001 | From 1946 to 1964 five Departments of State did the work of the modern Ministry of Defence: the Admiralty, the War Office, the Air Ministry, the Ministry of Aviation, and an earlier form of the Ministry of Defence. These departments merged in 1964; the defence functions of the Ministry of Aviation Supply merged into th... | [
{
"answer": "1946 to 1964",
"question": "During what years did the five Departments of State do the work of the modern Ministry of Defence?"
},
{
"answer": "the Admiralty, the War Office, the Air Ministry, the Ministry of Aviation, and an earlier form of the Ministry of Defence",
"question": "Wh... |
5,002 | The Ministers and Chiefs of the Defence Staff are supported by a number of civilian, scientific and professional military advisors. The Permanent Under-Secretary of State for Defence (generally known as the Permanent Secretary) is the senior civil servant at the MoD. His or her role is to ensure the MoD operates effect... | [
{
"answer": "The Ministers and Chiefs of the Defence Staff",
"question": "Who is supported by civilian, scientific, and professional military advisors?"
},
{
"answer": "Permanent Secretary",
"question": "What is the Permanent Under-Secretary of State for Defence generally known as?"
},
{
... |
5,003 | The current Chief of the Defence Staff, the professional head of the British Armed Forces, is General Sir Nicholas Houghton, late Green Howards. He is supported by the Vice Chief of the Defence Staff, by the professional heads of the three services of HM Armed Forces and by the Commander of Joint Forces Command. | [
{
"answer": "General Sir Nicholas Houghton",
"question": "What is the name of the person who is the current Chief of the Defence Staff?"
},
{
"answer": "Chief of the Defence Staff",
"question": "Who is the professional head of the British Armed Forces?"
},
{
"answer": "HM Armed Forces",
... |
5,004 | There are also three Deputy Chiefs of the Defence Staff with particular remits, Deputy Chief of the Defence Staff (Capability), Deputy CDS (Personnel and Training) and Deputy CDS (Operations). The Surgeon General, represents the Defence Medical Services on the Defence Staff, and is the clinical head of that service. | [
{
"answer": "three",
"question": "How many Deputy Chiefs of the Defence Staff are there?"
},
{
"answer": "Deputy Chief of the Defence Staff (Capability), Deputy CDS (Personnel and Training) and Deputy CDS (Operations)",
"question": "What are the three Deputy Chiefs of the Defence Staff?"
},
... |
5,005 | Additionally, there are a number of Assistant Chiefs of Defence Staff, including the Assistant Chief of the Defence Staff (Reserves and Cadets) and the Defence Services Secretary in the Royal Household of the Sovereign of the United Kingdom, who is also the Assistant Chief of Defence Staff (Personnel). | [
{
"answer": "Cadets",
"question": "One of the Assistant Chiefs of the Defence Staff is for Reserves and what?"
},
{
"answer": "the Defence Services Secretary in the Royal Household of the Sovereign of the United Kingdom",
"question": "The Personnel Chief is also known as what?"
},
{
"ans... |
5,006 | The 1998 Strategic Defence Review and the 2003 Delivering Security in a Changing World White Paper outlined the following posture for the British Armed Forces: | [
{
"answer": "1998",
"question": "In what year was there a Strategic Defence Review?"
},
{
"answer": "Delivering Security in a Changing World White Paper",
"question": "What paper was published in 2003?"
},
{
"answer": "British Armed Forces",
"question": "Which part of the Britsh gove... |
5,007 | The MoD has since been regarded as a leader in elaborating the post-Cold War organising concept of "defence diplomacy". As a result of the Strategic Defence and Security Review 2010, Prime Minister David Cameron signed a 50-year treaty with French President Nicolas Sarkozy that would have the two countries co-operate i... | [
{
"answer": "defence diplomacy",
"question": "In what concept is the MoD considered a leader?"
},
{
"answer": "David Cameron",
"question": "Who was the PM of Britain in 2010?"
},
{
"answer": "Nicolas Sarkozy",
"question": "Who was the president of France in 2010?"
},
{
"answe... |
5,008 | The Strategic Defence and Security Review 2015 included £178 billion investment in new equipment and capabilities. The review set a defence policy with four primary missions for the Armed Forces: | [
{
"answer": "£178 billion",
"question": "How much was the investment in new equipment and capabilities worth?"
},
{
"answer": "2015",
"question": "In which year was a £178 billion investment made?"
},
{
"answer": "four",
"question": "How many primary missions were included in the 201... |
5,009 | Following the end of the Cold War, the threat of direct conventional military confrontation with other states has been replaced by terrorism. Sir Richard Dannatt predicted British forces to be involved in combating "predatory non-state actors" for the foreseeable future, in what he called an "era of persistent conflict... | [
{
"answer": "terrorism",
"question": "What was the new threat that arose after the end of the Cold War?"
}
] |
5,010 | Dannatt criticised a remnant "Cold War mentality", with military expenditures based on retaining a capability against a direct conventional strategic threat; He said currently only 10% of the MoD's equipment programme budget between 2003 and 2018 was to be invested in the "land environment"—at a time when Britain was e... | [
{
"answer": "Cold War mentality",
"question": "Military spending that is based on conventional threats has been dismissed as what?"
},
{
"answer": "10%",
"question": "How much of the MoD's equipment budget is invested in the \"land environment\"?"
},
{
"answer": "Afghanistan and Iraq",
... |
5,012 | The Ministry of Defence is one of the United Kingdom's largest landowners, owning 227,300 hectares of land and foreshore (either freehold or leasehold) at April 2014, which was valued at "about £20 billion". The MoD also has "rights of access" to a further 222,000 hectares. In total, this is about 1.8% of the UK land m... | [
{
"answer": "227,300 hectares",
"question": "How much land is owned by the MoD?"
},
{
"answer": "£20 billion",
"question": "How much is the land owned by the MoD worth?"
},
{
"answer": "1.8%",
"question": "The MoD owns or has rights of access to what percentage of the UK's total land... |
5,013 | The defence estate is divided as training areas & ranges (84.0%), research & development (5.4%), airfields (3.4%), barracks & camps (2.5%), storage & supply depots (1.6%), and other (3.0%). These are largely managed by the Defence Infrastructure Organisation. | [
{
"answer": "84.0%",
"question": "What percentage of the defence estate makes up training areas and ranges?"
},
{
"answer": "storage & supply depots",
"question": "What makes up the smallest portion of the defence estate?"
},
{
"answer": "(3.4%",
"question": "What percentage of the d... |
5,014 | The headquarters of the MoD are in Whitehall and are now known as Main Building. This structure is neoclassical in style and was originally built between 1938 and 1959 to designs by Vincent Harris to house the Air Ministry and the Board of Trade. The northern entrance in Horse Guards Avenue is flanked by two monumental... | [
{
"answer": "Whitehall",
"question": "In what city are the headquarters of the MoD?"
},
{
"answer": "Vincent Harris",
"question": "Who designed the headquarters of the MoD?"
},
{
"answer": "Charles Wheeler",
"question": "Who designed the statues that are on either side of the norther... |
5,015 | Henry VIII's wine cellar at the Palace of Whitehall, built in 1514–1516 for Cardinal Wolsey, is in the basement of Main Building, and is used for entertainment. The entire vaulted brick structure of the cellar was encased in steel and concrete and relocated nine feet to the west and nearly 19 feet (5.8 m) deeper in 194... | [
{
"answer": "Henry VIII",
"question": "Who had a wine cellar at the Palace of Whitehall?"
},
{
"answer": "the basement of Main Building",
"question": "Where is Henry VIII's wine cellar?"
},
{
"answer": "1514–1516",
"question": "When was the cellar in the basement of Main Building bui... |
5,016 | The most notable fraud conviction was that of Gordon Foxley, head of defence procurement at the Ministry of Defence from 1981 to 1984. Police claimed he received at least £3.5m in total in corrupt payments, such as substantial bribes from overseas arms contractors aiming to influence the allocation of contracts. | [
{
"answer": "Gordon Foxley",
"question": "Who in the MoD was convicted of fraud?"
},
{
"answer": "head of defence procurement",
"question": "What position was held by Foxley?"
},
{
"answer": "1981 to 1984",
"question": "What years was Foxley employed by the MoD?"
},
{
"answer... |
5,018 | The MoD has been criticised for an ongoing fiasco, having spent £240m on eight Chinook HC3 helicopters which only started to enter service in 2010, years after they were ordered in 1995 and delivered in 2001. A National Audit Office report reveals that the helicopters have been stored in air conditioned hangars in Brit... | [
{
"answer": "£240m",
"question": "How much did the MoD spend on Chinook helicopters?"
},
{
"answer": "1995",
"question": "When were the helicopters ordered?"
},
{
"answer": "National Audit Office",
"question": "Which office reported that the helicopters were being stored, rather than... |
5,019 | In April 2008, a £90m contract was signed with Boeing for a "quick fix" solution, so they can fly by 2010: QinetiQ will downgrade the Chinooks—stripping out some of their more advanced equipment. | [
{
"answer": "Boeing",
"question": "Which aircraft manufacturer got a contract with the MoD?"
},
{
"answer": "April 2008",
"question": "When was the Boeing contract signed?"
},
{
"answer": "QinetiQ",
"question": "Who is downgrading the Chinook helicopters?"
},
{
"answer": "£90... |
5,020 | In October 2009, the MoD was heavily criticized for withdrawing the bi-annual non-operational training £20m budget for the volunteer Territorial Army (TA), ending all non-operational training for 6 months until April 2010. The government eventually backed down and restored the funding. The TA provides a small percentag... | [
{
"answer": "October 2009",
"question": "When was the TA budget withdrawn?"
},
{
"answer": "£20m",
"question": "How much money was allocated to the volunteer Territorial Army?"
},
{
"answer": "April 2010",
"question": "When was the training for the TA supposed to resume?"
},
{
... |
5,021 | In 2013 it was found that the Ministry of Defence had overspent on its equipment budget by £6.5bn on orders that could take up to 39 years to fulfil. The Ministry of Defence has been criticised in the past for poor management and financial control, investing in projects that have taken up to 10 and even as much as 15 y... | [
{
"answer": "£6.5bn",
"question": "By how much did the MoD go over its equipment budget?"
},
{
"answer": "2013",
"question": "When was the overbudget amount discovered?"
},
{
"answer": "poor management and financial control",
"question": "What are some of the criticisms that have bee... |
5,022 | The term high definition once described a series of television systems originating from August 1936; however, these systems were only high definition when compared to earlier systems that were based on mechanical systems with as few as 30 lines of resolution. The ongoing competition between companies and nations to cre... | [
{
"answer": "1936",
"question": "The term \"high definition\" originally described televisions systems from what year?"
},
{
"answer": "mechanical systems with as few as 30 lines of resolution",
"question": "Earlier television systems were based on what?"
},
{
"answer": "20th",
"ques... |
5,024 | Colour broadcasts started at similarly higher resolutions, first with the US NTSC color system in 1953, which was compatible with the earlier monochrome systems and therefore had the same 525 lines of resolution. European standards did not follow until the 1960s, when the PAL and SECAM color systems were added to the m... | [
{
"answer": "1953,",
"question": "What year did color broadcasts start in the US?"
},
{
"answer": "525",
"question": "How many lines of resolution did the US NTSC color system have in 1953?"
},
{
"answer": "1960s",
"question": "When did Europe begin color broadcasts?"
},
{
"a... |
5,025 | The Nippon Hōsō Kyōkai (NHK, the Japan Broadcasting Corporation) began conducting research to "unlock the fundamental mechanism of video and sound interactions with the five human senses" in 1964, after the Tokyo Olympics. NHK set out to create an HDTV system that ended up scoring much higher in subjective tests than N... | [
{
"answer": "Nippon Hōsō Kyōkai",
"question": "What is the Japan Broadcasting Corporation called?"
},
{
"answer": "Nippon Hōsō Kyōkai",
"question": "What does NHK stand for in Japan?"
},
{
"answer": "1972",
"question": "What year was NHK Color created?"
},
{
"answer": "5:3",
... |
5,026 | There were four major HDTV systems tested by SMPTE in the late 1970s, and in 1979 an SMPTE study group released A Study of High Definition Television Systems: | [
{
"answer": "four",
"question": "How many major HDTV systems were tested by SMPTE in the late 70's?"
},
{
"answer": "SMPTE",
"question": "Who tested the four major HDTV systems in the late 1970's?"
},
{
"answer": "an SMPTE study group",
"question": "Who released A Study of High Defin... |
5,027 | Since the formal adoption of digital video broadcasting's (DVB) widescreen HDTV transmission modes in the early 2000s; the 525-line NTSC (and PAL-M) systems, as well as the European 625-line PAL and SECAM systems, are now regarded as standard definition television systems. | [
{
"answer": "digital video broadcasting",
"question": "What does DVB stand for?"
},
{
"answer": "early 2000s",
"question": "When was widescreen HDTV transmission modes formally adopted?"
},
{
"answer": "SECAM systems",
"question": "In addition to the 625-line PAL system, what Europea... |
5,028 | In 1949, France started its transmissions with an 819 lines system (with 737 active lines). The system was monochrome only, and was used only on VHF for the first French TV channel. It was discontinued in 1983. | [
{
"answer": "1949",
"question": "In what year did France start transmissions using and 819 line system?"
},
{
"answer": "France",
"question": "What country started transmissions using and 819 line system in 1949?"
},
{
"answer": "an 819 lines system",
"question": "What did France sta... |
5,029 | In 1958, the Soviet Union developed Тransformator (Russian: Трансформатор, meaning Transformer), the first high-resolution (definition) television system capable of producing an image composed of 1,125 lines of resolution aimed at providing teleconferencing for military command. It was a research project and the system... | [
{
"answer": "a research project",
"question": "In the end what was the Soviet Union's Transformator system used for?"
},
{
"answer": "1958",
"question": "When did the Soviet Union develop Transformator?"
},
{
"answer": "the Soviet Union",
"question": "Who developed Transformator in 1... |
5,030 | In 1979, the Japanese state broadcaster NHK first developed consumer high-definition television with a 5:3 display aspect ratio. The system, known as Hi-Vision or MUSE after its Multiple sub-Nyquist sampling encoding for encoding the signal, required about twice the bandwidth of the existing NTSC system but provided ab... | [
{
"answer": "1979",
"question": "In what year did NHK first develop consumer HD television with a 5:3 aspect ratio?"
},
{
"answer": "the Japanese state broadcaster NHK",
"question": "Who first developed consumer HD television with a 5:3 aspect ratio?"
},
{
"answer": "1989",
"question... |
5,031 | In 1981, the MUSE system was demonstrated for the first time in the United States, using the same 5:3 aspect ratio as the Japanese system. Upon visiting a demonstration of MUSE in Washington, US President Ronald Reagan was impressed and officially declared it "a matter of national interest" to introduce HDTV to the US. | [
{
"answer": "1981",
"question": "When was the MUSE system demonstrated in the US first?"
},
{
"answer": "5:3",
"question": "What aspect ratio did the MUSE system use when demonstrated in 1981?"
},
{
"answer": "President Ronald Reagan",
"question": "Which president declared it \"a mat... |
5,032 | Several systems were proposed as the new standard for the US, including the Japanese MUSE system, but all were rejected by the FCC because of their higher bandwidth requirements. At this time, the number of television channels was growing rapidly and bandwidth was already a problem. A new standard had to be more effici... | [
{
"answer": "their higher bandwidth requirements",
"question": "Why did the FCC reject systems such as MUSE?"
},
{
"answer": "television channels",
"question": "What was increasing and consuming a lot of bandwidth?"
},
{
"answer": "the FCC",
"question": "Who rejected systems such as ... |
5,033 | The limited standardization of analog HDTV in the 1990s did not lead to global HDTV adoption as technical and economic constraints at the time did not permit HDTV to use bandwidths greater than normal television. | [
{
"answer": "technical and economic",
"question": "What constraints kept HDTV from being widely adopted in the 90's?"
},
{
"answer": "use bandwidths greater than normal television",
"question": "What was HDTV not permitted to do in the 90's?"
}
] |
5,034 | Early HDTV commercial experiments, such as NHK's MUSE, required over four times the bandwidth of a standard-definition broadcast. Despite efforts made to reduce analog HDTV to about twice the bandwidth of SDTV, these television formats were still distributable only by satellite. | [
{
"answer": "over four times",
"question": "How much more bandwith was required from early HDTV commercial experiments than an SD broadcast?"
},
{
"answer": "about twice",
"question": "Efforts were made to reduce analog HDTV to how much of the bandwith of SDTV?"
},
{
"answer": "by satell... |
5,035 | In addition, recording and reproducing an HDTV signal was a significant technical challenge in the early years of HDTV (Sony HDVS). Japan remained the only country with successful public broadcasting of analog HDTV, with seven broadcasters sharing a single channel. | [
{
"answer": "seven",
"question": "How many broadcasters did Japan have sharing a single channel?"
},
{
"answer": "Japan",
"question": "Which country had successful public analog HDTV broadcasting?"
},
{
"answer": "recording and reproducing an HDTV signal",
"question": "What was parti... |
5,036 | Since 1972, International Telecommunication Union's radio telecommunications sector (ITU-R) had been working on creating a global recommendation for Analog HDTV. These recommendations, however, did not fit in the broadcasting bands which could reach home users. The standardization of MPEG-1 in 1993 also led to the acce... | [
{
"answer": "International Telecommunication Union's radio telecommunications sector",
"question": "What does ITU-R stand for?"
},
{
"answer": "Digital Video Broadcasting",
"question": "What does DVB stand for?"
},
{
"answer": "an alliance of broadcasters, consumer electronics manufactur... |
5,037 | DVB created first the standard for DVB-S digital satellite TV, DVB-C digital cable TV and DVB-T digital terrestrial TV. These broadcasting systems can be used for both SDTV and HDTV. In the US the Grand Alliance proposed ATSC as the new standard for SDTV and HDTV. Both ATSC and DVB were based on the MPEG-2 standard, al... | [
{
"answer": "ATSC",
"question": "What did the Grand Alliance propose as the new standard for SDTV and HDTV?"
},
{
"answer": "MPEG-2",
"question": "Which standard were ATSC and DVB based on?"
},
{
"answer": "DVB",
"question": "Who created the standard for DVB-2, DVB-C, and DVB-T?"
}... |
5,038 | In 1983, the International Telecommunication Union's radio telecommunications sector (ITU-R) set up a working party (IWP11/6) with the aim of setting a single international HDTV standard. One of the thornier issues concerned a suitable frame/field refresh rate, the world already having split into two camps, 25/50 Hz an... | [
{
"answer": "1983",
"question": "When did ITU-R start trying to work towards setting a single international HDTV standard?"
},
{
"answer": "setting a single international HDTV standard",
"question": "What did ITU-R start trying to do in 1983?"
},
{
"answer": "a suitable frame/field refre... |
5,039 | Initially the existing 5:3 aspect ratio had been the main candidate but, due to the influence of widescreen cinema, the aspect ratio 16:9 (1.78) eventually emerged as being a reasonable compromise between 5:3 (1.67) and the common 1.85 widescreen cinema format. An aspect ratio of 16:9 was duly agreed upon at the first ... | [
{
"answer": "16:9",
"question": "What aspect ratio was agreed upon due to the influence of widescreen cinema?"
},
{
"answer": "the IWP11/6 working party",
"question": "Who agreed upon the 16:9 aspect ratio?"
},
{
"answer": "widescreen cinema",
"question": "What was a leading factor i... |
5,040 | It also includes the alternative 1440×1152 HDMAC scan format. (According to some reports, a mooted 750-line (720p) format (720 progressively scanned lines) was viewed by some at the ITU as an enhanced television format rather than a true HDTV format, and so was not included, although 1920×1080i and 1280×720p systems fo... | [
{
"answer": "1440×1152 HDMAC",
"question": "What scan format is also included in MBAFF?"
},
{
"answer": "a mooted 750-line",
"question": "What was viewed by some as enhanced television format and not true HDTV format?"
},
{
"answer": "an enhanced television format",
"question": "A mo... |
5,042 | The first HDTV transmissions in Europe, albeit not direct-to-home, began in 1990, when the Italian broadcaster RAI used the HD-MAC and MUSE HDTV technologies to broadcast the 1990 FIFA World Cup. The matches were shown in 8 cinemas in Italy and 2 in Spain. The connection with Spain was made via the Olympus satellite li... | [
{
"answer": "1990",
"question": "When did the first HDTV transmissions happen in Europe?"
},
{
"answer": "FIFA World Cup",
"question": "What event was the first HDTV broadcast in Europe?"
},
{
"answer": "mid-1990s",
"question": "When did Europe abandon standard transmission?"
},
... |
5,043 | The first regular broadcasts started on January 1, 2004 when the Belgian company Euro1080 launched the HD1 channel with the traditional Vienna New Year's Concert. Test transmissions had been active since the IBC exhibition in September 2003, but the New Year's Day broadcast marked the official launch of the HD1 channel... | [
{
"answer": "January 1, 2004",
"question": "When did regular broadcasts start in Europe?"
},
{
"answer": "Vienna New Year's Concert",
"question": "What event was first broadcasted on January 1, 2004?"
},
{
"answer": "HD1",
"question": "The New Year's Day broadcast officially launched... |
5,044 | Euro1080, a division of the former and now bankrupt Belgian TV services company Alfacam, broadcast HDTV channels to break the pan-European stalemate of "no HD broadcasts mean no HD TVs bought means no HD broadcasts ..." and kick-start HDTV interest in Europe. The HD1 channel was initially free-to-air and mainly compris... | [
{
"answer": "Alfacam",
"question": "Euro1080 was a division of what former company?"
},
{
"answer": "\"no HD broadcasts mean no HD TVs bought means no HD broadcasts ...\"",
"question": "What \"chicken or the egg\" stalemate prompted Euro1080 to broadcast HDTV channels?"
},
{
"answer": "H... |
5,045 | These first European HDTV broadcasts used the 1080i format with MPEG-2 compression on a DVB-S signal from SES's Astra 1H satellite. Euro1080 transmissions later changed to MPEG-4/AVC compression on a DVB-S2 signal in line with subsequent broadcast channels in Europe. | [
{
"answer": "1080i format",
"question": "What format did the first European HDTV broadcast use?"
},
{
"answer": "MPEG-2",
"question": "What compression did the first European HDTV broadcast use?"
},
{
"answer": "DVB-S",
"question": "What signal did the first European HDTV broadcast u... |
5,046 | Despite delays in some countries, the number of European HD channels and viewers has risen steadily since the first HDTV broadcasts, with SES's annual Satellite Monitor market survey for 2010 reporting more than 200 commercial channels broadcasting in HD from Astra satellites, 185 million HD capable TVs sold in Europe ... | [
{
"answer": "185 million",
"question": "According to the 2010 Satellite Monitor market survey, how many HD capable TV's were sold in Europe?"
},
{
"answer": "20 million",
"question": "According to the 2010 Satellite Monitor market survey, how many European households were watching HD broadcasts?... |
5,047 | In December 2009 the United Kingdom became the first European country to deploy high definition content using the new DVB-T2 transmission standard, as specified in the Digital TV Group (DTG) D-book, on digital terrestrial television. | [
{
"answer": "the United Kingdom",
"question": "Which European country first deployed HD content using the new DVB-T2 standard?"
},
{
"answer": "December 2009",
"question": "When did the UK deploy HD content using the new DVB-T2 transmission standard?"
},
{
"answer": "DVB-T2",
"questi... |
5,048 | The Freeview HD service currently contains 10 HD channels (as of December 2013[update]) and was rolled out region by region across the UK in accordance with the digital switchover process, finally being completed in October 2012. However, Freeview HD is not the first HDTV service over digital terrestrial television in ... | [
{
"answer": "10",
"question": "How many HD channels did the Freeview HD service contain as of December 2013?"
},
{
"answer": "October 2012",
"question": "When was the digital switchover process completed in the UK?"
},
{
"answer": "Freeview HD",
"question": "Which service contains 10... |
5,049 | If all three parameters are used, they are specified in the following form: [frame size][scanning system][frame or field rate] or [frame size]/[frame or field rate][scanning system].[citation needed] Often, frame size or frame rate can be dropped if its value is implied from context. In this case, the remaining numeric... | [
{
"answer": "[frame size][scanning system][frame or field rate]",
"question": "What are the three HDTV parameters?"
},
{
"answer": "frame size or frame rate",
"question": "Which two parameters can be dropped if its value is implied from context?"
},
{
"answer": "if its value is implied f... |
5,050 | For example, 1920×1080p25 identifies progressive scanning format with 25 frames per second, each frame being 1,920 pixels wide and 1,080 pixels high. The 1080i25 or 1080i50 notation identifies interlaced scanning format with 25 frames (50 fields) per second, each frame being 1,920 pixels wide and 1,080 pixels high. The... | [
{
"answer": "1,920 pixels wide and 1,080 pixels high",
"question": "What size is each 1920x1080p25 frame?"
},
{
"answer": "25",
"question": "The 1920x1080p25 notion identifies progressive scanning format with how many frames per second?"
},
{
"answer": "25",
"question": "The 1080i25 ... |
5,051 | 50 Hz systems support three scanning rates: 50i, 25p and 50p. 60 Hz systems support a much wider set of frame rates: 59.94i, 60i, 23.976p, 24p, 29.97p, 30p, 59.94p and 60p. In the days of standard definition television, the fractional rates were often rounded up to whole numbers, e.g. 23.976p was often called 24p, or 5... | [
{
"answer": "50i, 25p and 50p",
"question": "What three scanning rates do 50 Hz systems support?"
},
{
"answer": "60 Hz",
"question": "Which system suports 59.94i, 60i, 23.976p, 24p, 29.97p, 30p, 59.94p, and 60p"
},
{
"answer": "whole numbers",
"question": "SD television fractional r... |
5,052 | For the commercial naming of a product, the frame rate is often dropped and is implied from context (e.g., a 1080i television set). A frame rate can also be specified without a resolution. For example, 24p means 24 progressive scan frames per second, and 50i means 25 interlaced frames per second. | [
{
"answer": "the frame rate",
"question": "What is usually dropped for the commercial naming of an HDTV product?"
},
{
"answer": "24 progressive scan frames per second",
"question": "What does 24p mean?"
},
{
"answer": "25 interlaced frames per second",
"question": "What does 50i mea... |
5,053 | There is no single standard for HDTV color support. Colors are typically broadcast using a (10-bits per channel) YUV color space but, depending on the underlying image generating technologies of the receiver, are then subsequently converted to a RGB color space using standardized algorithms. When transmitted directly t... | [
{
"answer": "no",
"question": "Is there a single standard for HDTV color support?"
},
{
"answer": "YUV",
"question": "Before being converted to RGB, colors are ususally broadcasted using what color space?"
},
{
"answer": "a RGB color space",
"question": "Colors are typically broadcas... |
5,054 | At a minimum, HDTV has twice the linear resolution of standard-definition television (SDTV), thus showing greater detail than either analog television or regular DVD. The technical standards for broadcasting HDTV also handle the 16:9 aspect ratio images without using letterboxing or anamorphic stretching, thus increasi... | [
{
"answer": "twice",
"question": "At least how many times more linear resolution does HDTV have over SDTV?"
},
{
"answer": "letterboxing or anamorphic stretching",
"question": "HDTV increases the effective image resolution by not using what?"
},
{
"answer": "standard-definition televisio... |
5,055 | A very high resolution source may require more bandwidth than available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage and transmission systems will distort the received picture, when compared to the uncompressed source. | [
{
"answer": "fidelity",
"question": "If more bandwith is required than is available, a very high resolution source my not be able to transmitted without loss of what?"
},
{
"answer": "distort the received picture",
"question": "The compression used in all HDTV storage and transmission systems wi... |
5,056 | The optimum format for a broadcast depends upon the type of videographic recording medium used and the image's characteristics. For best fidelity to the source the transmitted field ratio, lines, and frame rate should match those of the source. | [
{
"answer": "the type of videographic recording medium used and the image's characteristics",
"question": "A broadcasts optimum format depends on what two things?"
},
{
"answer": "transmitted field ratio, lines, and frame rate",
"question": "For best fidelity to the source, what three things sho... |
5,057 | PAL, SECAM and NTSC frame rates technically apply only to analogue standard definition television, not to digital or high definition broadcasts. However, with the roll out of digital broadcasting, and later HDTV broadcasting, countries retained their heritage systems. HDTV in former PAL and SECAM countries operates at ... | [
{
"answer": "analogue standard",
"question": "PAL, SECAM, and NTSC frame rates apply to what definition televisions?"
},
{
"answer": "digital or high definition",
"question": "PAL, SECAM, and NTSC frame rates do not apply to what broadcasts?"
},
{
"answer": "25/50 Hz",
"question": "I... |
5,058 | Standard 35mm photographic film used for cinema projection has a much higher image resolution than HDTV systems, and is exposed and projected at a rate of 24 frames per second (frame/s). To be shown on standard television, in PAL-system countries, cinema film is scanned at the TV rate of 25 frame/s, causing a speedup o... | [
{
"answer": "24 frames per second",
"question": "At what rate is standard 35mm photographic film exposed and projected?"
},
{
"answer": "25 frame/s",
"question": "To be shown on SDTV in PAL-system countries, at what rate is cinema film scanned?"
},
{
"answer": "3:2 Pulldown",
"questi... |
5,059 | Non-cinematic HDTV video recordings intended for broadcast are typically recorded either in 720p or 1080i format as determined by the broadcaster. 720p is commonly used for Internet distribution of high-definition video, because most computer monitors operate in progressive-scan mode. 720p also imposes less strenuous s... | [
{
"answer": "720p or 1080i",
"question": "What two formats are typically used to recorde non-cinematic HDTV video intended for broadcast?"
},
{
"answer": "720p",
"question": "Which format is typically used for internet distribution of HD video?"
},
{
"answer": "progressive-scan",
"qu... |
5,060 | In the US, residents in the line of sight of television station broadcast antennas can receive free, over the air programming with a television set with an ATSC tuner (most sets sold since 2009 have this). This is achieved with a TV aerial, just as it has been since the 1940s except now the major network signals are br... | [
{
"answer": "ATSC",
"question": "In the US, what kind of tuner is needed for residents to receive free, over the air programming?"
},
{
"answer": "the change to digital terrestrial broadcasts",
"question": "Laws regarding antennas were upated before what?"
},
{
"answer": "home owners' as... |
5,061 | Additionally, cable-ready TV sets can display HD content without using an external box. They have a QAM tuner built-in and/or a card slot for inserting a CableCARD. | [
{
"answer": "an external box",
"question": "HD content can be displayed by cable-ready TVs without using what?"
},
{
"answer": "HD content",
"question": "Without using an external box, cable-ready TVs can display what?"
},
{
"answer": "a QAM tuner built-in and/or a card slot for insertin... |
5,062 | High-definition image sources include terrestrial broadcast, direct broadcast satellite, digital cable, IPTV (including GoogleTV Roku boxes and AppleTV or built into "Smart Televisions"), Blu-ray video disc (BD), and internet downloads. | [
{
"answer": "IPTV",
"question": "Roku and AppleTV are examples of what?"
},
{
"answer": "High-definition image sources",
"question": "Internet downloads, Blu-ray videos, and Apple TV are examples of what?"
},
{
"answer": "High-definition image sources",
"question": "Terrestrial broad... |
5,063 | Sony's PlayStation 3 has extensive HD compatibility because of its built in Blu-ray disc based player, so does Microsoft's Xbox 360 with the addition of Netflix and Windows Media Center HTPC streaming capabilities, and the Zune marketplace where users can rent or purchase digital HD content. Recently, Nintendo released... | [
{
"answer": "because of its built in Blu-ray disc based player",
"question": "Why does the PlayStation 3 have extensive HD compatibility?"
},
{
"answer": "Netflix and Windows Media Center HTPC streaming capabilities, and the Zune marketplace",
"question": "In addition to having a Blu-ray player ... |
5,064 | HDTV can be recorded to D-VHS (Digital-VHS or Data-VHS), W-VHS (analog only), to an HDTV-capable digital video recorder (for example DirecTV's high-definition Digital video recorder, Sky HD's set-top box, Dish Network's VIP 622 or VIP 722 high-definition Digital video recorder receivers, or TiVo's Series 3 or HD record... | [
{
"answer": "an HDTV-capable digital video recorder",
"question": "Sky HD's set-top box, TiVo's Series 3, and Dish Network's VIP 622 are examples of what?"
},
{
"answer": "receiving or recording two or more broadcasts at a time in HDTV format",
"question": "Some cable boxes are capable of doing ... |
5,065 | The massive amount of data storage required to archive uncompressed streams meant that inexpensive uncompressed storage options were not available to the consumer. In 2008, the Hauppauge 1212 Personal Video Recorder was introduced. This device accepts HD content through component video inputs and stores the content in ... | [
{
"answer": "2008",
"question": "When was the Hauppauge 1212 Personal Video Recorder introduced?"
},
{
"answer": "in MPEG-2 format in a .ts file or in a Blu-ray compatible format .m2ts file",
"question": "How does the Personal Video Recorder store content?"
},
{
"answer": "'as broadcast'... |
5,066 | Analog tape recorders with bandwidth capable of recording analog HD signals, such as W-VHS recorders, are no longer produced for the consumer market and are both expensive and scarce in the secondary market. | [
{
"answer": "analog HD",
"question": "W-VHS recorders are capable of recording what kinds of signals?"
},
{
"answer": "Analog tape",
"question": "What kind of recorder is no longer produced for the consumer market?"
},
{
"answer": "expensive and scarce",
"question": "In the secondary... |
5,067 | In the United States, as part of the FCC's plug and play agreement, cable companies are required to provide customers who rent HD set-top boxes with a set-top box with "functional" FireWire (IEEE 1394) on request. None of the direct broadcast satellite providers have offered this feature on any of their supported boxes... | [
{
"answer": "a set-top box with \"functional\" FireWire (IEEE 1394) on request",
"question": "Prior to 2004, what were US cable companies required to provide customers who rent HD set-top boxes?"
},
{
"answer": "July 2004",
"question": "When were boxes with \"functional\" FireWire no longer incl... |
5,068 | It has been used for thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers (which are strong in tension) embedded in a matrix of lignin which resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or... | [
{
"answer": "fuel",
"question": "In addition to being used to build things, what has wood been used for over thousands of years?"
},
{
"answer": "cellulose",
"question": "What kind of strong fibers are part of the composite of wood?"
},
{
"answer": "lignin",
"question": "What's the m... |
5,069 | The Earth contains about 434 billion cubic meters of growing stock forest, 47% of which is commercial. As an abundant, carbon-neutral renewable resource, woody materials have been of intense interest as a source of renewable energy. In 1991, approximately 3.5 cubic kilometers of wood were harvested. Dominant uses were ... | [
{
"answer": "434 billion",
"question": "How many cubic meters of growing stock forest are there on the planet?"
},
{
"answer": "47%",
"question": "What percentage of the Earth's stock forest is commercial?"
},
{
"answer": "furniture",
"question": "In addition to buildings, what is wo... |
5,070 | A 2011 discovery in the Canadian province of New Brunswick uncovered the earliest known plants to have grown wood, approximately 395 to 400 million years ago. Wood can be dated by carbon dating and in some species by dendrochronology to make inferences about when a wooden object was created. | [
{
"answer": "2011",
"question": "What year were the earliest plants that grew wood discovered?"
},
{
"answer": "New Brunswick",
"question": "In which Canadian province were the oldest woody plants found?"
},
{
"answer": "carbon dating",
"question": "If dendrochronology can't be used,... |
5,071 | People have used wood for millennia for many purposes, primarily as a fuel or as a construction material for making houses, tools, weapons, furniture, packaging, artworks, and paper. The year-to-year variation in tree-ring widths and isotopic abundances gives clues to the prevailing climate at that time. | [
{
"answer": "construction material",
"question": "What has been the primary purpose of wood for millennia other than fuel?"
},
{
"answer": "houses",
"question": "What is often made of wood that provides shelter to people?"
},
{
"answer": "tree-ring widths",
"question": "For clues abo... |
5,072 | Wood, in the strict sense, is yielded by trees, which increase in diameter by the formation, between the existing wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots. This process is known as secondary growth; it is the result of cell division in the vascular cambium, ... | [
{
"answer": "trees",
"question": "Where does wood come from?"
},
{
"answer": "woody layers",
"question": "What forms in a tree to increase its diameter?"
},
{
"answer": "secondary growth",
"question": "What is the process of trees growing out to get bigger around called?"
},
{
... |
5,073 | If there are differences within a growth ring, then the part of a growth ring nearest the center of the tree, and formed early in the growing season when growth is rapid, is usually composed of wider elements. It is usually lighter in color than that near the outer portion of the ring, and is known as earlywood or spri... | [
{
"answer": "wider",
"question": "If a growth ring has differences over one season, would the part nearest the tree's center be narrower or wider?"
},
{
"answer": "earlywood",
"question": "What name, besides springwood, is used for the part of a growth ring formed in the beginning of the growing... |
5,074 | A knot is a particular type of imperfection in a piece of wood; it will affect the technical properties of the wood, usually reducing the local strength and increasing the tendency for splitting along the wood grain, but may be exploited for visual effect. In a longitudinally sawn plank, a knot will appear as a roughly... | [
{
"answer": "knot",
"question": "What is the sort of circular imperfection in a piece of wood called?"
},
{
"answer": "strength",
"question": "What property of wood does a knot usually reduce in the wood around it?"
},
{
"answer": "longitudinally",
"question": "In what direction is w... |
5,075 | In the tree a knot is either the base of a side branch or a dormant bud. A knot (when the base of a side branch) is conical in shape (hence the roughly circular cross-section) with the inner tip at the point in stem diameter at which the plant's vascular cambium was located when the branch formed as a bud. | [
{
"answer": "a dormant bud",
"question": "Other than the base of a side branch, what tree feature causes a knot?"
},
{
"answer": "conical",
"question": "What shape is the knot formed by a side branch's base?"
},
{
"answer": "diameter",
"question": "What measurement of a stem determin... |
5,076 | During the development of a tree, the lower limbs often die, but may remain attached for a time, sometimes years. Subsequent layers of growth of the attaching stem are no longer intimately joined with the dead limb, but are grown around it. Hence, dead branches produce knots which are not attached, and likely to drop o... | [
{
"answer": "die",
"question": "What will the lower limbs of a tree usually do during development?"
},
{
"answer": "years",
"question": "For what length of time can a dead lower limb stay attached to a tree?"
},
{
"answer": "around it",
"question": "Rather than being joined to the li... |
5,077 | In grading lumber and structural timber, knots are classified according to their form, size, soundness, and the firmness with which they are held in place. This firmness is affected by, among other factors, the length of time for which the branch was dead while the attaching stem continued to grow. | [
{
"answer": "grading",
"question": "What's the process in which knots are classified called?"
},
{
"answer": "size",
"question": "Along with firmness, soundness, and form, what property of a knot is classified?"
},
{
"answer": "firmness",
"question": "What property of knots does the ... |
5,078 | Knots do not necessarily influence the stiffness of structural timber, this will depend on the size and location. Stiffness and elastic strength are more dependent upon the sound wood than upon localized defects. The breaking strength is very susceptible to defects. Sound knots do not weaken wood when subject to compre... | [
{
"answer": "defects",
"question": "What is wood's breaking strength susceptible to? "
},
{
"answer": "stiffness",
"question": "Depending on the placement and size of a knot, what property of structural timber can be affected?"
},
{
"answer": "sound wood",
"question": "What do stiffn... |
5,079 | In some decorative applications, wood with knots may be desirable to add visual interest. In applications where wood is painted, such as skirting boards, fascia boards, door frames and furniture, resins present in the timber may continue to 'bleed' through to the surface of a knot for months or even years after manufac... | [
{
"answer": "interest",
"question": "What positive visual component can knots sometimes add to decorative pieces?"
},
{
"answer": "bleed",
"question": "What term is used to describe what knots can do to affect the finish of things made from wood even when they've been painted?"
},
{
"ans... |
5,080 | Heartwood (or duramen) is wood that as a result of a naturally occurring chemical transformation has become more resistant to decay. Heartwood formation occurs spontaneously (it is a genetically programmed process). Once heartwood formation is complete, the heartwood is dead. Some uncertainty still exists as to whether... | [
{
"answer": "Heartwood",
"question": "What's another word for \"duramen\"?"
},
{
"answer": "decay",
"question": "What is heartwood naturally resistant to?"
},
{
"answer": "spontaneously",
"question": "How does heartwood formation occur due to its being genetically programmed?"
},
... |
5,081 | Heartwood is often visually distinct from the living sapwood, and can be distinguished in a cross-section where the boundary will tend to follow the growth rings. For example, it is sometimes much darker. However, other processes such as decay or insect invasion can also discolor wood, even in woody plants that do not ... | [
{
"answer": "growth rings",
"question": "In what part of a tree's cross-section is heartwood visible?"
},
{
"answer": "darker",
"question": "What simple color distinction can heartwood have that makes it stand out from living wood in a tree?"
},
{
"answer": "decay",
"question": "Alon... |
5,082 | Sapwood (or alburnum) is the younger, outermost wood; in the growing tree it is living wood, and its principal functions are to conduct water from the roots to the leaves and to store up and give back according to the season the reserves prepared in the leaves. However, by the time they become competent to conduct wate... | [
{
"answer": "alburnum",
"question": "What term is interchangeable with \"sapwood\"?"
},
{
"answer": "younger",
"question": "Is sapwood the younger or older wood in a tree?"
},
{
"answer": "water",
"question": "What essential liquid is the sapwood tasked with carrying around a tree?"
... |
5,083 | The term heartwood derives solely from its position and not from any vital importance to the tree. This is evidenced by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change come... | [
{
"answer": "thin",
"question": "If a tree starts forming heartwood right away, will its sapwood layer be thin or thick?"
},
{
"answer": "position",
"question": "What property of heartwood that has nothing to do with how important it is to trees got it its name?"
},
{
"answer": "thick",
... |
5,084 | No definite relation exists between the annual rings of growth and the amount of sapwood. Within the same species the cross-sectional area of the sapwood is very roughly proportional to the size of the crown of the tree. If the rings are narrow, more of them are required than where they are wide. As the tree gets large... | [
{
"answer": "crown",
"question": "What part of a tree is the cross-sectional area of the sapwood approximately proportional to?"
},
{
"answer": "narrow",
"question": "Are more rings necessary if they're narrow or wide?"
},
{
"answer": "thinner",
"question": "As a tree grows bigger, i... |
5,085 | When a tree is very young it is covered with limbs almost, if not entirely, to the ground, but as it grows older some or all of them will eventually die and are either broken off or fall off. Subsequent growth of wood may completely conceal the stubs which will however remain as knots. No matter how smooth and clear a ... | [
{
"answer": "limbs",
"question": "What usually covers the whole trunk of a very young tree?"
},
{
"answer": "knots",
"question": "What evidence of the stubs of the limbs a tree loses can always be seen in the wood?"
},
{
"answer": "heartwood",
"question": "In a very old tree, are you... |
5,086 | It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds, and in a few instances thousands, of years old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penet... | [
{
"answer": "decay",
"question": "What do broken limbs and deep wounds open a door for in a tree?"
},
{
"answer": "the trunk",
"question": "Decay can spread to all of what part of a tree?"
},
{
"answer": "larvae",
"question": "What growth stage of insects bore holes into trees?"
},... |
5,087 | If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside... | [
{
"answer": "youth",
"question": "In what stage of its life does a tree usually grow the fastest?"
},
{
"answer": "narrower",
"question": "As a tree ages, do its growth rings usually get wider or narrower?"
},
{
"answer": "crown",
"question": "What part of a tree opens and spreads ou... |
5,088 | Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspo... | [
{
"answer": "differ",
"question": "When a big tree is cut up, will the pieces of wood differ or all be the same?"
},
{
"answer": "heartwood",
"question": "In a large log, will the heartwood or sapwood usually be stronger and tougher?"
},
{
"answer": "sapwood",
"question": "If you nee... |
5,089 | In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co... | [
{
"answer": "heartwood",
"question": "When trees have a visible difference in color between sapwood and heartwood, which is darker?"
},
{
"answer": "chemical substances",
"question": "What is deposited naturally in heartwood that changes its color?"
},
{
"answer": "conspicuous",
"que... |
5,090 | Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o... | [
{
"answer": "Longleaf Pine",
"question": "What type of tree has resin that makes it stronger when it dries?"
},
{
"answer": "fat lighter",
"question": "What's the funny name for resin-saturated heartwood?"
},
{
"answer": "rot",
"question": "What is fat lighter practically impervious ... |
5,091 | Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f... | [
{
"answer": "latewood",
"question": "Which of the wood in a growth ring is usually darker?"
},
{
"answer": "density",
"question": "Which property of a tree's wood that gives clues about its strength and hardness can be judged by it's color?"
},
{
"answer": "coniferous",
"question": "... |
5,092 | Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ... | [
{
"answer": "diseased",
"question": "What condition does an abnormal color usually indicate in wood?"
},
{
"answer": "unsoundness",
"question": "What other property can you assume of wood that is diseased?"
},
{
"answer": "insect attacks",
"question": "What causes the black checked p... |
5,093 | In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains 8–16% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry. | [
{
"answer": "water",
"question": "What does wood retain in its cell walls despite being air-dried?"
},
{
"answer": "16",
"question": "Air-dried wood keeps up to what percentage of the water in its cell walls?"
},
{
"answer": "oven-dried",
"question": "What kind of dried wood retains ... |
5,094 | The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect. | [
{
"answer": "softer",
"question": "Often the water in wood makes it more pliable and what else?"
},
{
"answer": "rawhide",
"question": "What material sometimes used for dog chews reacts similarly to wood because of its water content?"
},
{
"answer": "paper",
"question": "What materia... |
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