Problem: Richard Feynman:

After the war, Feynman declined an offer from the Institute for Advanced Study in Princeton, New Jersey, despite the presence there of such distinguished faculty members as Albert Einstein, Kurt Godel and John von Neumann. Feynman followed Hans Bethe, instead, to Cornell University, where Feynman taught theoretical physics from 1945 to 1950. During a temporary depression following the destruction of Hiroshima by the bomb produced by the Manhattan Project, he focused on complex physics problems, not for utility, but for self-satisfaction. One of these was analyzing the physics of a twirling, nutating dish as it is moving through the air. His work during this period, which used equations of rotation to express various spinning speeds, proved important to his Nobel Prizewinning work, yet because he felt burned out and had turned his attention to less immediately practical problems, he was surprised by the offers of professorships from other renowned universities.

Which colleague did Feynman follow to Cornell?
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A: Hans Bethe

Problem: Most Western languages (particularly those with writing systems based on the Latin, Cyrillic, Greek, Coptic, and Armenian alphabets) use letter cases in their written form as an aid to clarity. Scripts using two separate cases are also called bicameral scripts. Many other writing systems make no distinction between majuscules and minuscules a system called unicameral script or unicase. This includes most syllabic and other non-alphabetic scripts. The Georgian alphabet is special since it used to be bicameral, but today is mostly used in a unicameral way.
What are scripts that utilized two seperate cases called?
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Answer: bicameral

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1940, non-Hispanic whites constituted 86.8% of the city's population. The population peaked at more than two million residents in 1950, then began to decline with the restructuring of industry, which led to the loss of many middle-class union jobs. In addition, suburbanization had been drawing off many of the wealthier residents to outlying railroad commuting towns and newer housing. Revitalization and gentrification of neighborhoods began in the late 1970s and continues into the 21st century, with much of the development in the Center City and University City areas of the city. After many of the old manufacturers and businesses left Philadelphia or shut down, the city started attracting service businesses and began to more aggressively market itself as a tourist destination. Glass-and-granite skyscrapers were built in Center City. Historic areas such as Independence National Historical Park located in Old City and Society Hill were renovated during the reformist mayoral era of the 1950s through the 1980s. They are now among the most desirable living areas of Center City. This has slowed the city's 40-year population decline after it lost nearly one-quarter of its population.
Why did the population decline after this time?
A: the loss of many middle-class union jobs

Context and question: Characters with diacritical marks can generally be represented either as a single precomposed character or as a decomposed sequence of a base letter plus one or more non-spacing marks. For example, e (precomposed e with macron and acute above) and e (e followed by the combining macron above and combining acute above) should be rendered identically, both appearing as an e with a macron and acute accent, but in practice, their appearance may vary depending upon what rendering engine and fonts are being used to display the characters. Similarly, underdots, as needed in the romanization of Indic, will often be placed incorrectly[citation needed]. Unicode characters that map to precomposed glyphs can be used in many cases, thus avoiding the problem, but where no precomposed character has been encoded the problem can often be solved by using a specialist Unicode font such as Charis SIL that uses Graphite, OpenType, or AAT technologies for advanced rendering features.
What is the name of the rendering technology OpenType uses?
Answer: unanswerable

Question: The Chicago Transit Authority's elevated train running through Evanston is called the Purple Line, taking its name from Northwestern's school color. The Foster and Davis stations are within walking distance of the southern end of the campus, while the Noyes station is close to the northern end of the campus. The Central station is close to Ryan Field, Northwestern's football stadium. The Evanston Davis Street Metra station serves the Northwestern campus in downtown Evanston and the Evanston Central Street Metra station is near Ryan Field. Pace Suburban Bus Service and the CTA have several bus routes that run through or near the Evanston campus.
Is there an answer to this question: Which train stations are within driving distance of the southern end of campus?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with constant bitrate. Average bitrate is VBR implemented as a compromise between the two: the bitrate is allowed to vary for more consistent quality, but is controlled to remain near an average value chosen by the user, for predictable file sizes. Although an MP3 decoder must support VBR to be standards compliant, historically some decoders have bugs with VBR decoding, particularly before VBR encoders became widespread.
An average bit rate is used when who choses an average value for the encoder to use?
A:
the user