Problem: United States dollar:

The colloquialism "buck"(s) (much like the British word "quid"(s, pl) for the pound sterling) is often used to refer to dollars of various nations, including the U.S. dollar. This term, dating to the 18th century, may have originated with the colonial leather trade. It may also have originated from a poker term. "Greenback" is another nickname originally applied specifically to the 19th century Demand Note dollars created by Abraham Lincoln to finance the costs of the Civil War for the North. The original note was printed in black and green on the back side. It is still used to refer to the U.S. dollar (but not to the dollars of other countries). Other well-known names of the dollar as a whole in denominations include "greenmail", "green" and "dead presidents" (the last because deceased presidents are pictured on most bills).

What color other than red was used on the backside of the original note?
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A: unanswerable


Problem: Glass has the ability to refract, reflect, and transmit light following geometrical optics, without scattering it. It is used in the manufacture of lenses and windows. Common glass has a refraction index around 1.5. This may be modified by adding low-density materials such as boron, which lowers the index of refraction (see crown glass), or increased (to as much as 1.8) with high-density materials such as (classically) lead oxide (see flint glass and lead glass), or in modern uses, less toxic oxides of zirconium, titanium, or barium. These high-index glasses (inaccurately known as "crystal" when used in glass vessels) cause more chromatic dispersion of light, and are prized for their diamond-like optical properties.
What is the refraction index of typical glass?
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Answer: 1.5


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In theory, the stadtholders were freely appointed by and subordinate to the states of each province. However, in practice the princes of Orange of the House of Orange-Nassau, beginning with William the Silent, were always chosen as stadtholders of most of the provinces. Zeeland and usually Utrecht had the same stadtholder as Holland.
Who appointed the princes of Orange?
A: unanswerable


Context and question: The English term comics derives from the humorous (or "comic") work which predominated in early American newspaper comic strips; usage of the term has become standard for non-humorous works as well. The term "comic book" has a similarly confusing history: they are most often not humorous; nor are they regular books, but rather periodicals. It is common in English to refer to the comics of different cultures by the terms used in their original languages, such as manga for Japanese comics, or bandes dessinées for French-language Franco-Belgian comics.
What is the term that the French use for the comics out of Japan?
Answer: unanswerable


Question: To determine what information in an audio signal is perceptually irrelevant, most lossy compression algorithms use transforms such as the modified discrete cosine transform (MDCT) to convert time domain sampled waveforms into a transform domain. Once transformed, typically into the frequency domain, component frequencies can be allocated bits according to how audible they are. Audibility of spectral components calculated using the absolute threshold of hearing and the principles of simultaneous masking—the phenomenon wherein a signal is masked by another signal separated by frequency—and, in some cases, temporal masking—where a signal is masked by another signal separated by time. Equal-loudness contours may also be used to weight the perceptual importance of components. Models of the human ear-brain combination incorporating such effects are often called psychoacoustic models.
Is there an answer to this question: What may be used to weight the importance of cosine?

Answer: unanswerable


Problem: Edmund Burke:

Among the reasons this speech was so greatly admired was its passage on Lord Bathurst (1684–1775); Burke describes an angel in 1704 prophesying to Bathurst the future greatness of England and also of America: "Young man, There is America – which at this day serves little more than to amuse you with stories of savage men, and uncouth manners; yet shall, before you taste of death, shew itself equal to the whole of that commerce which now attracts the envy of the world". Samuel Johnson was so irritated at hearing it continually praised, that he made a parody of it, where the devil appears to a young Whig and predicts that in short time, Whiggism will poison even the paradise of America!

Who was impressed by Bathurst's prophesy?
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A:
unanswerable