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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.
Who was the first to liquidize hydrogen?
A: James Dewar

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In Britain a number of architects are active in the neoclassical style. Two new university Libraries, Quinlan Terry's Maitland Robinson Library at Downing College and ADAM Architecture's Sackler Library illustrate that the approach taken can range from the traditional, in the former case, to the unconventional, in the latter case. Recently, Prince Charles came under controversy for promoting a classically designed development on the land of the former Chelsea Barracks in London. Writing to the Qatari Royal family (who were funding the development through the property development company Qatari Diar) he condemned the accepted modernist plans, instead advocating a classical approach. His appeal was met with success and the plans were withdrawn. A new design by architecture house Dixon Jones is currently being drafted.
Is neoclassical design current in Britain?
A: a number of architects are active in the neoclassical

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Israel is served by two international airports, Ben Gurion International Airport, the country's main hub for international air travel near Tel Aviv-Yafo, Ovda Airport in the south, as well as several small domestic airports. Ben Gurion, Israel's largest airport, handled over 12.1 million passengers in 2010. On the Mediterranean coast, Haifa Port is the country's oldest and largest port, while Ashdod Port is one of the few deep water ports in the world built on the open sea. In addition to these, the smaller Port of Eilat is situated on the Red Sea, and is used mainly for trading with Far East countries.
How many international airports are in Israel?
A: two

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The roles and responsibilities of the minority leader are not well-defined. To a large extent, the functions of the minority leader are defined by tradition and custom. A minority leader from 1931 to 1939, Representative Bertrand Snell, R-N.Y., provided this "job description": "He is spokesman for his party and enunciates its policies. He is required to be alert and vigilant in defense of the minority's rights. It is his function and duty to criticize constructively the policies and programs of the majority, and to this end employ parliamentary tactics and give close attention to all proposed legislation."
What are some of the duties of a majority leader?
A:
unanswerable