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Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow".
Where is the oldest evidence of pure zinc?
A: Zawar

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Communal shelters never housed more than one seventh of Greater London residents, however. Peak use of the Underground as shelter was 177,000 on 27 September 1940, and a November 1940 census of London found that about 4% of residents used the Tube and other large shelters; 9% in public surface shelters; and 27% in private home shelters, implying that the remaining 60% of the city likely stayed at home. The government distributed Anderson shelters until 1941 and that year began distributing the Morrison shelter, which could be used inside homes.:190
What year did the government start giving out Morrison shelters?
A: 1941

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Louis did not leave a son as heir after his death in 1382. Instead, he named as his heir the young prince Sigismund of Luxemburg, who was 11 years old. The Hungarian nobility did not accept his claim, and the result was an internal war. Sigismund eventually achieved total control of Hungary and established his court in Buda and Visegrad. Both palaces were rebuilt and improved, and were considered the richest of the time in Europe. Inheriting the throne of Bohemia and the Holy Roman Empire, Sigismund continued conducting his politics from Hungary, but he was kept busy fighting the Hussites and the Ottoman Empire, which was becoming a menace to Europe in the beginning of the 15th century.
How old was Sigismund of Luxemburg when he was named heir?
A: 11

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Of the territories of Poland annexed by the Soviet Union between 1939 and 1940, the region around Biaystok and a minor part of Galicia east of the San river around Przemysl were returned to the Polish state at the end of World War II. Of all other territories annexed by the USSR in 193940, the ones detached from Finland (Karelia, Petsamo), Estonia (Ingrian area and Petseri County) and Latvia (Abrene) remained part of the Russian Federation, the successor state of the Soviet Union, after 1991. Northern Bukovina, Southern Bessarabia and Hertza remain part of Ukraine.
What regions never remained part of the Soviet Union?
A:
unanswerable