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Antarctica is the coldest of Earth's continents. The coldest natural temperature ever recorded on Earth was −89.2 °C (−128.6 °F) at the Soviet (now Russian) Vostok Station in Antarctica on 21 July 1983. For comparison, this is 10.7 °C (20 °F) colder than subliming dry ice at one atmosphere of partial pressure, but since CO2 only makes up 0.039% of air, temperatures of less than −150 °C (−238 °F) would be needed to produce dry ice snow in Antarctica. Antarctica is a frozen desert with little precipitation; the South Pole itself receives less than 10 cm (4 in) per year, on average. Temperatures reach a minimum of between −80 °C (−112 °F) and −89.2 °C (−128.6 °F) in the interior in winter and reach a maximum of between 5 °C (41 °F) and 15 °C (59 °F) near the coast in summer. Sunburn is often a health issue as the snow surface reflects almost all of the ultraviolet light falling on it. Given the latitude, long periods of constant darkness or constant sunlight create climates unfamiliar to human beings in much of the rest of the world.
What does CO2 make up 0.39% of?
A: unanswerable

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Above the main portal there is generally a large window, like that at York Minster, or a group of windows such as those at Ripon Cathedral. In France there is generally a rose window like that at Reims Cathedral. Rose windows are also often found in the façades of churches of Spain and Italy, but are rarer elsewhere and are not found on the façades of any English Cathedrals. The gable is usually richly decorated with arcading or sculpture or, in the case of Italy, may be decorated with the rest of the façade, with polychrome marble and mosaic, as at Orvieto Cathedral.
Which Italian cathedral displays polychrome marble and mosaic on the floor?
A: unanswerable

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Northwestern has roughly 225,000 alumni in all branches of business, government, law, science, education, medicine, media, and the performing arts. Among Northwestern's more notable alumni are U.S. Senator and presidential candidate George McGovern, Nobel Prize–winning economist George J. Stigler, Nobel Prize–winning novelist Saul Bellow, Pulitzer Prize–winning composer and diarist Ned Rorem, the much-decorated composer Howard Hanson, Deputy Prime Minister of Turkey Ali Babacan, the historian and novelist Wilma Dykeman, and the founder of the presidential prayer breakfast Abraham Vereide. U.S. Supreme Court Associate Justice John Paul Stevens, Supreme Court Justice and Ambassador to the United Nations Arthur Joseph Goldberg, and Governor of Illinois and Democratic presidential candidate Adlai Stevenson are among the graduates of the Northwestern School of Law. Many Northwestern alumni play or have played important roles in Chicago and Illinois, such as former Illinois governor and convicted felon Rod Blagojevich, Chicago Bulls and Chicago White Sox owner Jerry Reinsdorf, and theater director Mary Zimmerman. Northwestern alumnus David J. Skorton currently serves as president of Cornell University. Rahm Emanuel, the mayor of Chicago and former White House Chief of Staff, earned a Masters in Speech and Communication in 1985.
Which of Northwestern's alumni is notable for becoming the Illinois Governor and convicted felon?
A: Rod Blagojevich

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On 1 March 1951 Mao sent a cable to Stalin, in which he emphasized the difficulties faced by Chinese forces and the urgent need for air cover, especially over supply lines. Apparently impressed by the Chinese war effort, Stalin finally agreed to supply two air force divisions, three anti-aircraft divisions, and six thousand trucks. PVA troops in Korea continued to suffer severe logistical problems throughout the war. In late April Peng Dehuai sent his deputy, Hong Xuezhi, to brief Zhou Enlai in Beijing. What Chinese soldiers feared, Hong said, was not the enemy, but that they had nothing to eat, no bullets to shoot, and no trucks to transport them to the rear when they were wounded. Zhou attempted to respond to the PVA's logistical concerns by increasing Chinese production and improving methods of supply, but these efforts were never completely sufficient. At the same time, large-scale air defense training programs were carried out, and the Chinese Air Force began to participate in the war from September 1951 onward.
What was a great concern of many Chinese troops?
A:
they had nothing to eat