I know that the answer to the question "What did Britain have control over in the Middle East in 1951?" is in "In 1951, the Conservative Party returned to power in Britain, under the leadership of Winston Churchill. Churchill and the Conservatives believed that Britain's position as a world power relied on the continued existence of the empire, with the base at the Suez Canal allowing Britain to maintain its pre-eminent position in the Middle East in spite of the loss of India. However, Churchill could not ignore Gamal Abdul Nasser's new revolutionary government of Egypt that had taken power in 1952, and the following year it was agreed that British troops would withdraw from the Suez Canal zone and that Sudan would be granted self-determination by 1955, with independence to follow. Sudan was granted independence on 1 January 1956.". Can you tell me what it is?
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Answer: Suez Canal

I know that the answer to the question "What was produced as a joint effort?" is in "Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. Heavy water, which consists of deuterium in the place of regular hydrogen, was discovered by Urey's group in 1932. Francois Isaac de Rivaz built the first de Rivaz engine, an internal combustion engine powered by a mixture of hydrogen and oxygen in 1806. Edward Daniel Clarke invented the hydrogen gas blowpipe in 1819. The Dobereiner's lamp and limelight were invented in 1823.". Can you tell me what it is?
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Answer: tritium

I know that the answer to the question "What kind of difference was there in knights and the szlachta in Poland?" is in "Around the 14th century, there was little difference between knights and the szlachta in Poland. Members of the szlachta had the personal obligation to defend the country (pospolite ruszenie), thereby becoming the kingdom's most privileged social class. Inclusion in the class was almost exclusively based on inheritance.". Can you tell me what it is?
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Answer:
there was little difference