Problem: Internet service provider:

Network hardware, software and specifications, as well as the expertise of network management personnel are important in ensuring that data follows the most efficient route, and upstream connections work reliably. A tradeoff between cost and efficiency is possible.[citation needed]

What trade-off is not possible?
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A: unanswerable

Problem: Canadian football:

On the field at the beginning of a play are two teams of 12 (unlike 11 in American football). The team in possession of the ball is the offence and the team defending is referred to as the defence. Play begins with a backwards pass through the legs (the snap) by a member of the offensive team, to another member of the offensive team. This is usually the quarterback or punter, but a "direct snap" to a running back is also not uncommon. If the quarterback or punter receives the ball, he may then do any of the following:

What is the running back in possession of the ball called?
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A: unanswerable

Problem: Multiracial American:

Colonial records of French and Spanish slave ships and sales, and plantation records in all the former colonies, often have much more information about slaves, from which researchers are reconstructing slave family histories. Genealogists have begun to find plantation records, court records, land deeds and other sources to trace African-American families and individuals before 1870. As slaves were generally forbidden to learn to read and write, black families passed along oral histories, which have had great persistence. Similarly, Native Americans did not generally learn to read and write English, although some did in the nineteenth century. Until 1930, census enumerators used the terms free people of color and mulatto to classify people of apparent mixed race. When those terms were dropped, as a result of the lobbying by the Southern Congressional bloc, the Census Bureau used only the binary classifications of black or white, as was typical in segregated southern states.

What has helped geneologists researching slaves?
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A: Colonial records of French and Spanish slave ships and sales, and plantation records in all the former colonies

Problem: Karl Popper:

While there is some dispute as to the matter of influence, Popper had a long-standing and close friendship with economist Friedrich Hayek, who was also brought to the London School of Economics from Vienna. Each found support and similarities in the other's work, citing each other often, though not without qualification. In a letter to Hayek in 1944, Popper stated, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski." Popper dedicated his Conjectures and Refutations to Hayek. For his part, Hayek dedicated a collection of papers, Studies in Philosophy, Politics, and Economics, to Popper, and in 1982 said, "...ever since his Logik der Forschung first came out in 1934, I have been a complete adherent to his general theory of methodology."

Who did Hayek write a letter to in 1944?
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A:
unanswerable