Problem: Translation:

Comparison of a back-translation with the original text is sometimes used as a check on the accuracy of the original translation, much as the accuracy of a mathematical operation is sometimes checked by reversing the operation. But the results of such reverse-translation operations, while useful as approximate checks, are not always precisely reliable. Back-translation must in general be less accurate than back-calculation because linguistic symbols (words) are often ambiguous, whereas mathematical symbols are intentionally unequivocal.

How are mathematical operations checked?
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A: by reversing the operation

Problem: Unicode:

The UCS-2 and UTF-16 encodings specify the Unicode Byte Order Mark (BOM) for use at the beginnings of text files, which may be used for byte ordering detection (or byte endianness detection). The BOM, code point U+FEFF has the important property of unambiguity on byte reorder, regardless of the Unicode encoding used; U+FFFE (the result of byte-swapping U+FEFF) does not equate to a legal character, and U+FEFF in other places, other than the beginning of text, conveys the zero-width non-break space (a character with no appearance and no effect other than preventing the formation of ligatures).

What changes the important property in BOM?
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A: unanswerable

Problem: United States dollar:

The early currency of the United States did not exhibit faces of presidents, as is the custom now; although today, by law, only the portrait of a deceased individual may appear on United States currency. In fact, the newly formed government was against having portraits of leaders on the currency, a practice compared to the policies of European monarchs. The currency as we know it today did not get the faces they currently have until after the early 20th century; before that "heads" side of coinage used profile faces and striding, seated, and standing figures from Greek and Roman mythology and composite Native Americans. The last coins to be converted to profiles of historic Americans were the dime (1946) and the Dollar (1971).

When did modern day currency start getting the Native Americans they have?
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A: unanswerable

Problem: Charleston, South Carolina:

Founded in 1670 as Charles Town in honor of King Charles II of England, Charleston adopted its present name in 1783. It moved to its present location on Oyster Point in 1680 from a location on the west bank of the Ashley River known as Albemarle Point. By 1690, Charles Town was the fifth-largest city in North America, and it remained among the 10 largest cities in the United States through the 1840 census. With a 2010 census population of 120,083 (and a 2014 estimate of 130,113), current trends put Charleston as the fastest-growing municipality in South Carolina. The population of the Charleston metropolitan area, comprising Berkeley, Charleston, and Dorchester Counties, was counted by the 2014 estimate at 727,689 the third-largest in the state and the 78th-largest metropolitan statistical area in the United States.

Charles Town was named after which queen?
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A:
unanswerable