Problem: Han dynasty:

The waterwheel appeared in Chinese records during the Han. As mentioned by Huan Tan in about 20 AD, they were used to turn gears that lifted iron trip hammers, and were used in pounding, threshing and polishing grain. However, there is no sufficient evidence for the watermill in China until about the 5th century. The Nanyang Commandery Administrator Du Shi (d. 38 AD) created a waterwheel-powered reciprocator that worked the bellows for the smelting of iron. Waterwheels were also used to power chain pumps that lifted water to raised irrigation ditches. The chain pump was first mentioned in China by the philosopher Wang Chong in his 1st-century-AD Balanced Discourse.

During what era did the waterwheel first appear in recordings?
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A: Han

Problem: The American studies program reflected the worldwide anti-Communist ideological struggle. Norman Holmes Pearson, who worked for the Office of Strategic Studies in London during World War II, returned to Yale and headed the new American studies program, in which scholarship quickly became an instrument of promoting liberty. Popular among undergraduates, the program sought to instruct them in the fundamentals of American civilization and thereby instill a sense of nationalism and national purpose. Also during the 1940s and 1950s, Wyoming millionaire William Robertson Coe made large contributions to the American studies programs at Yale University and at the University of Wyoming. Coe was concerned to celebrate the 'values' of the Western United States in order to meet the "threat of communism."
Where did Norman Holmes Pearson work after Yale?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1933, the Orthodox Church of Greece officially declared that being a Freemason constitutes an act of apostasy and thus, until he repents, the person involved with Freemasonry cannot partake of the Eucharist. This has been generally affirmed throughout the whole Eastern Orthodox Church. The Orthodox critique of Freemasonry agrees with both the Roman Catholic and Protestant versions: "Freemasonry cannot be at all compatible with Christianity as far as it is a secret organisation, acting and teaching in mystery and secret and deifying rationalism."
In what year did the Orthodox Church of Greece declare that being a Freemason constituted an act of apostasy?
A: 1933

Context and question: Prior to Confederation in 1867, residents of the colonies in what is now Canada served as regular members of French and British forces and in local militia groups. The latter aided in the defence of their respective territories against attacks by other European powers, Aboriginal peoples, and later American forces during the American Revolutionary War and War of 1812, as well as in the Fenian raids, Red River Rebellion, and North-West Rebellion. Consequently, the lineages of some Canadian army units stretch back to the early 19th century, when militia units were formed to assist in the defence of British North America against invasion by the United States.
Who aided in defence during the Fenian Rebellion?
Answer: unanswerable

Question: In principle, comprehensive schools were conceived as "neighbourhood" schools for all students in a specified catchment area. Current education reforms with Academies Programme, Free Schools and University Technical Colleges will no doubt have some impact on the comprehensive ideal but it is too early to say to what degree.
Is there an answer to this question: What is a word that can be used to describe the scope of a comprehensive school's discharge?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Some rock formations in the path of a glacier are sculpted into small hills called roche moutonnee, or "sheepback" rock. Roche moutonnee are elongated, rounded, and asymmetrical bedrock knobs that can be produced by glacier erosion. They range in length from less than a meter to several hundred meters long. Roche moutonnee have a gentle slope on their up-glacier sides and a steep to vertical face on their down-glacier sides. The glacier abrades the smooth slope on the upstream side as it flows along, but tears loose and carries away rock from the downstream side via plucking.
What are steep on their upside and and gentle on their down side?
A:
unanswerable