Problem: Emotion:

The history of emotions has become an increasingly popular topic recently, with some scholars arguing that it is an essential category of analysis, not unlike class, race, or gender. Historians, like other social scientists, assume that emotions, feelings and their expressions are regulated in different ways by both different cultures and different historical times, and constructivist school of history claims even that some sentiments and meta-emotions, for example Schadenfreude, are learnt and not only regulated by culture. Historians of emotion trace and analyse the changing norms and rules of feeling, while examining emotional regimes, codes, and lexicons from social, cultural or political history perspectives. Others focus on the history of medicine, science or psychology. What somebody can and may feel (and show) in a given situation, towards certain people or things, depends on social norms and rules. It is thus historically variable and open to change. Several research centers have opened in the past few years in Germany, England, Spain, Sweden and Australia.

Along with class and race, what is regarded as an essential category of historical analysis?
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A: gender

Problem: Multiracial American:

Interracial relationships have had a long history in North America and the United States, beginning with the intermixing of European explorers and soldiers, who took native women as companions. After European settlement increased, traders and fur trappers often married or had unions with women of native tribes. In the 17th century, faced with a continuing, critical labor shortage, colonists primarily in the Chesapeake Bay Colony, imported Africans as laborers, sometimes as indentured servants and, increasingly, as slaves. African slaves were also imported into New York and other northern ports by the Dutch and later English. Some African slaves were freed by their masters during these early years.

What has a long history in Europe?
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A: unanswerable

Problem: The Legend of Zelda: Twilight Princess:

In four months, Aonuma's team managed to present realistic horseback riding,[l] which Nintendo later revealed to the public with a trailer at Electronic Entertainment Expo 2004. The game was scheduled to be released the next year, and was no longer a follow-up to The Wind Waker; a true sequel to it was released for the Nintendo DS in 2007, in the form of Phantom Hourglass. Miyamoto explained in interviews that the graphical style was chosen to satisfy demand, and that it better fit the theme of an older incarnation of Link. The game runs on a modified The Wind Waker engine.

What was the name of the second Aonuma game?
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A: unanswerable

Problem: Planck constant:

There are both practical and theoretical difficulties in determining h. The practical difficulties can be illustrated by the fact that the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another. The most likely reason is that the measurement uncertainty for one (or both) of the methods has been estimated too low it is (or they are) not as precise as is currently believed but for the time being there is no indication which method is at fault.

Which method is at fault or the discrepancy?
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A:
there is no indication which method is at fault