Problem: Atlantic City, New Jersey:

In the wake of the United States' economic downturn and the legalization of gambling in adjacent and nearby states (including Delaware, Maryland, New York, and Pennsylvania), four casino closures took place in 2014: the Atlantic Club on January 13; the Showboat on August 31; the Revel, which was Atlantic City's second-newest casino, on September 2; and Trump Plaza, which originally opened in 1984, and was the poorest performing casino in the city, on September 16.

What was the name of Atlantic City's second-newest casino that ultimately closed in 2014?
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A: Revel

Problem: Group (mathematics):

The convergence of these various sources into a uniform theory of groups started with Camille Jordan's Traite des substitutions et des equations algebriques (1870). Walther von Dyck (1882) introduced the idea of specifying a group by means of generators and relations, and was also the first to give an axiomatic definition of an "abstract group", in the terminology of the time. As of the 20th century, groups gained wide recognition by the pioneering work of Ferdinand Georg Frobenius and William Burnside, who worked on representation theory of finite groups, Richard Brauer's modular representation theory and Issai Schur's papers. The theory of Lie groups, and more generally locally compact groups was studied by Hermann Weyl, Elie Cartan and many others. Its algebraic counterpart, the theory of algebraic groups, was first shaped by Claude Chevalley (from the late 1930s) and later by the work of Armand Borel and Jacques Tits.

When did the uniform theory of groups develop from different sources?
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A: 1870

Problem: Utrecht:

From the middle of the 3rd century Germanic tribes regularly invaded the Roman territories. Around 275 the Romans could no longer maintain the northern border and Utrecht was abandoned. Little is known about the next period 270650. Utrecht is first spoken of again several centuries after the Romans left. Under the influence of the growing realms of the Franks, during Dagobert I's reign in the 7th century, a church was built within the walls of the Roman fortress. In ongoing border conflicts with the Frisians this first church was destroyed.

Who started invading Roman territories during the mid 300's?
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A: unanswerable

Problem: Vacuum:

Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is lower than atmospheric pressure. The Latin term in vacuo is used to describe an object as being in what would otherwise be a vacuum.

What is the definition of atmospheric pressure?
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A:
unanswerable