Problem: Detroit:

Beginning with its incorporation in 1802, Detroit has had a total of 74 mayors. Detroit's last mayor from the Republican Party was Louis Miriani, who served from 1957 to 1962. In 1973, the city elected its first black mayor, Coleman Young. Despite development efforts, his combative style during his five terms in office was not well received by many suburban residents. Mayor Dennis Archer, a former Michigan Supreme Court Justice, refocused the city's attention on redevelopment with a plan to permit three casinos downtown. By 2008, three major casino resort hotels established operations in the city.

Who was Detroit's last Republican mayor?
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A: Louis Miriani

Problem: Macintosh:

Notwithstanding these technical and commercial successes on the Macintosh platform, their systems remained fairly expensive, making them less competitive in light of the falling costs of components that made IBM PC compatibles cheaper and accelerated their adoption. In 1989, Jean-Louis Gassee had steadfastly refused to lower the profit margins on Mac computers, then there was a component shortage that rocked the exponentially-expanding PC industry that year, forcing Apple USA head Allan Loren to cut prices which dropped Apple's margins. Microsoft Windows 3.0 was released in May 1990, the first iteration of Windows which had a feature set and performance comparable to the significantly costlier Macintosh. Furthermore, Apple had created too many similar models that confused potential buyers; at one point the product lineup was subdivided into Classic, LC, II, Quadra, Performa, and Centris models, with essentially the same computer being sold under a number of different names.

What problem rocked the PC industry in 1998?
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A: unanswerable

Problem: John von Neumann:

Von Neumann worked on lattice theory between 1937 and 1939. Von Neumann provided an abstract exploration of dimension in completed complemented modular topological lattices: "Dimension is determined, up to a positive linear transformation, by the following two properties. It is conserved by perspective mappings ("perspectivities") and ordered by inclusion. The deepest part of the proof concerns the equivalence of perspectivity with "projectivity by decomposition"of which a corollary is the transitivity of perspectivity." Garrett Birkhoff writes: "John von Neumann's brilliant mind blazed over lattice theory like a meteor".

What did von Neumann work on in 1937 - 39?
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A: lattice theory

Problem: Uranium:

On 2 December 1942, as part of the Manhattan Project, another team led by Enrico Fermi was able to initiate the first artificial self-sustained nuclear chain reaction, Chicago Pile-1. Working in a lab below the stands of Stagg Field at the University of Chicago, the team created the conditions needed for such a reaction by piling together 400 short tons (360 metric tons) of graphite, 58 short tons (53 metric tons) of uranium oxide, and six short tons (5.5 metric tons) of uranium metal, a majority of which was supplied by Westinghouse Lamp Plant in a makeshift production process.

What project was Fermi working for?
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A:
Manhattan