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Tucson's primary electrical power source is a coal and natural gas power-plant managed by Tucson Electric Power that is situated within the city limits on the south-western boundary of Davis-Monthan Air-force base adjacent to Interstate-10. The air pollution generated has raised some concerns as the Sundt operating station has been online since 1962 as is exempt from many pollution standards and controls due to its age. Solar has been gaining ground in Tucson with its ideal over 300 days of sunshine climate. Federal, state, and even local utility credits and incentives have also enticed residents to equip homes with solar systems. Davis-Monthan AFB has a 3.3 Megawatt (MW) ground-mounted solar photovoltaic (PV) array and a 2.7 MW rooftop-mounted PV array, both of which are located in the Base Housing area. The base will soon have the largest solar-generating capacity in the United States Department of Defense after awarding a contract on September 10, 2010, to SunEdison to construct a 14.5 MW PV field on the northwestern side of the base.
How many days of sunshine does Tucson get each year?
A: over 300

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Richmond is not home to any major league professional sports teams, but since 2013, the Washington Redskins of the National Football League have held their summer training camp in the city. There are also several minor league sports in the city, including the Richmond Kickers of the USL Professional Division (third tier of American soccer) and the Richmond Flying Squirrels of the Class AA Eastern League of Minor League Baseball (an affiliate of the San Francisco Giants). The Kickers began playing in Richmond in 1993, and currently play at City Stadium. The Squirrels opened their first season at The Diamond on April 15, 2010. From 1966 through 2008, the city was home to the Richmond Braves, a AAA affiliate of the Atlanta Braves of Major League Baseball, until the franchise relocated to Georgia.
What is the home ground of the Richmond Kickers?
A: City Stadium

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Von Neumann introduced the study of rings of operators, through the von Neumann algebras. A von Neumann algebra is a *-algebra of bounded operators on a Hilbert space that is closed in the weak operator topology and contains the identity operator. The von Neumann bicommutant theorem shows that the analytic definition is equivalent to a purely algebraic definition as an algebra of symmetries. The direct integral was introduced in 1949 by John von Neumann. One of von Neumann's analyses was to reduce the classification of von Neumann algebras on separable Hilbert spaces to the classification of factors.
What does the von Neumann bicommutant theorem show?
A: the analytic definition is equivalent to a purely algebraic definition as an algebra of symmetries.

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Rapid increases in a number of commodity prices followed the collapse in the housing bubble. The price of oil nearly tripled from $50 to $147 from early 2007 to 2008, before plunging as the financial crisis began to take hold in late 2008. Experts debate the causes, with some attributing it to speculative flow of money from housing and other investments into commodities, some to monetary policy, and some to the increasing feeling of raw materials scarcity in a fast-growing world, leading to long positions taken on those markets, such as Chinese increasing presence in Africa. An increase in oil prices tends to divert a larger share of consumer spending into gasoline, which creates downward pressure on economic growth in oil importing countries, as wealth flows to oil-producing states. A pattern of spiking instability in the price of oil over the decade leading up to the price high of 2008 has been recently identified. The destabilizing effects of this price variance has been proposed as a contributory factor in the financial crisis.
What did the price of oil began doing when the financial crisis began to take hold in late 2008?
A:
plunging