Problem: 51st state:

Cuba, like many Spanish territories, wanted to break free from Spain. A pro-independence movement in Cuba was supported by the U.S., and Cuban guerrilla leaders wanted annexation to the United States, but Cuban revolutionary leader José Martí called for Cuban nationhood. When the U.S. battleship Maine sank in Havana Harbor, the U.S. blamed Spain and the Spanish–American War broke out in 1898. After the U.S. won, Spain relinquished claim of sovereignty over territories, including Cuba. The U.S. administered Cuba as a protectorate until 1902. Several decades later in 1959, the corrupt Cuban government of U.S.-backed Fulgencio Batista was overthrown by Fidel Castro. Castro installed a Marxist–Leninist government allied with the Soviet Union, which has been in power ever since.

Who wanted to break from the U.S.?
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A: unanswerable


Problem: Super Nintendo Entertainment System:

The cartridge media of the console is officially referred to as Game Pak in most Western regions, and as Cassette (カセット, Kasetto?) in Japan and parts of Latin America. While the SNES can address 128 Mbit,[f] only 117.75 Mbit are actually available for cartridge use. A fairly normal mapping could easily address up to 95 Mbit of ROM data (48 Mbit at FastROM speed) with 8 Mbit of battery-backed RAM. However, most available memory access controllers only support mappings of up to 32 Mbit. The largest games released (Tales of Phantasia and Star Ocean) contain 48 Mbit of ROM data, while the smallest games contain only 2 Mbit.

What are SNES game cartridges officially called in Japan?
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A: Cassette


Problem: Solar energy:

Off-grid PV systems have traditionally used rechargeable batteries to store excess electricity. With grid-tied systems, excess electricity can be sent to the transmission grid, while standard grid electricity can be used to meet shortfalls. Net metering programs give household systems a credit for any electricity they deliver to the grid. This is handled by 'rolling back' the meter whenever the home produces more electricity than it consumes. If the net electricity use is below zero, the utility then rolls over the kilowatt hour credit to the next month. Other approaches involve the use of two meters, to measure electricity consumed vs. electricity produced. This is less common due to the increased installation cost of the second meter. Most standard meters accurately measure in both directions, making a second meter unnecessary.

Why is a second meter usually unnecessary to monitor electricity use?
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A: Most standard meters accurately measure in both directions


Problem: Military history of the United States:

The military history of the American side of the war involved different strategies over the years. The bombing campaigns of the Air Force were tightly controlled by the White House for political reasons, and until 1972 avoided the main Northern cities of Hanoi and Haiphong and concentrated on bombing jungle supply trails, especially the Ho Chi Minh Trail. The most controversial Army commander was William Westmoreland whose strategy involved systematic defeat of all enemy forces in the field, despite heavy American casualties that alienated public opinion back home.

 Who helped orchestrate bombing campaigns in the Chinese War?
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A:
unanswerable