Problem: Charles Pollak (born Karol Pollak), the inventor of the first electrolytic capacitors, found out that the oxide layer on an aluminum anode remained stable in a neutral or alkaline electrolyte, even when the power was switched off. In 1896 he filed a patent for an "Electric liquid capacitor with aluminum electrodes." Solid electrolyte tantalum capacitors were invented by Bell Laboratories in the early 1950s as a miniaturized and more reliable low-voltage support capacitor to complement their newly invented transistor.
Who invented the second electrolytic capacitor?
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Answer: unanswerable

Problem: The Estonian dialects are divided into two groups the northern and southern dialects, historically associated with the cities of Tallinn in the north and Tartu in the south, in addition to a distinct kirderanniku dialect, that of the northeastern coast of Estonia.
What is the city where the eastern dialect was historically spoken?
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Answer: unanswerable

Problem: Greenware ceramics made from celadon had been made in the area since the 3rd-century Jin dynasty, but it returned to prominenceparticularly in Longquanduring the Southern Song and Yuan. Longquan greenware is characterized by a thick unctuous glaze of a particular bluish-green tint over an otherwise undecorated light-grey porcellaneous body that is delicately potted. Yuan Longquan celadons feature a thinner, greener glaze on increasingly large vessels with decoration and shapes derived from Middle Eastern ceramic and metalwares. These were produced in large quantities for the Chinese export trade to Southeast Asia, the Middle East, and (during the Ming) Europe. By the Ming, however, production was notably deficient in quality. It is in this period that the Longquan kilns declined, to be eventually replaced in popularity and ceramic production by the kilns of Jingdezhen in Jiangxi.
What period did Longquan ceramics decline?
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Answer:
the Ming