The problem: Answer a question about this article:
Feynman attended Far Rockaway High School, a school in Far Rockaway, Queens also attended by fellow Nobel laureates Burton Richter and Baruch Samuel Blumberg. Upon starting high school, Feynman was quickly promoted into a higher math class. An unspecified school-administered IQ test estimated his IQ at 123high, but "merely respectable" according to biographer James Gleick. When he turned 15, he taught himself trigonometry, advanced algebra, infinite series, analytic geometry, and both differential and integral calculus. In high school he was developing the mathematical intuition behind his Taylor series of mathematical operators. Before entering college, he was experimenting with and deriving mathematical topics such as the half-derivative using his own notation.
Feyman taught himself many math subjects, including Trigonometry at what age?
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The answer: 15

The problem: Answer a question about this article:
During the oil boom of the 1970s, Nigeria joined OPEC and the huge revenue generated made the economy richer. Despite huge revenues from oil production and sale, the military administration did little to improve the standard of living of the population, help small and medium businesses, or invest in infrastructure. As oil revenues fuelled the rise of federal subventions to states, the federal government became the centre of political struggle and the threshold of power in the country. As oil production and revenue rose, the Nigerian government became increasingly dependent on oil revenues and the international commodity markets for budgetary and economic concerns. It did not develop other sources of the economy for economic stability. That spelled doom to federalism in Nigeria.
Which oil group did Nigeria join?
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The answer: OPEC

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Most Western and Commonwealth militaries integrate air defence purely with the traditional services, of the military (i.e. army, navy and air force), as a separate arm or as part of artillery. In the United States Army for instance, air defence is part of the artillery arm, while in the Pakistan Army, it was split off from Artillery to form a separate arm of its own in 1990. This is in contrast to some (largely communist or ex-communist) countries where not only are there provisions for air defence in the army, navy and air force but there are specific branches that deal only with the air defence of territory, for example, the Soviet PVO Strany. The USSR also had a separate strategic rocket force in charge of nuclear intercontinental ballistic missiles.
What type of countries have set branches for territorial air defence?
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The answer: largely communist or ex-communist

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Short-term memory is also known as working memory. Short-term memory allows recall for a period of several seconds to a minute without rehearsal. Its capacity is also very limited: George A. Miller (1956), when working at Bell Laboratories, conducted experiments showing that the store of short-term memory was 72 items (the title of his famous paper, "The magical number 72"). Modern estimates of the capacity of short-term memory are lower, typically of the order of 45 items; however, memory capacity can be increased through a process called chunking. For example, in recalling a ten-digit telephone number, a person could chunk the digits into three groups: first, the area code (such as 123), then a three-digit chunk (456) and lastly a four-digit chunk (7890). This method of remembering telephone numbers is far more effective than attempting to remember a string of 10 digits; this is because we are able to chunk the information into meaningful groups of numbers. This may be reflected in some countries in the tendency to display telephone numbers as several chunks of two to four numbers.
Why do some countries display numbers in chunks of two to four numbers?
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The answer:
because we are able to chunk the information into meaningful groups of numbers