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Since the beginning of the study of electricity non conductive materials like glass, porcelain, paper and mica have been used as insulators. These materials some decades later were also well-suited for further use as the dielectric for the first capacitors. Paper capacitors made by sandwiching a strip of impregnated paper between strips of metal, and rolling the result into a cylinder were commonly used in the late 19century; their manufacture started in 1876, and they were used from the early 20th century as decoupling capacitors in telecommunications (telephony).
Besides porcelain, paper and mica, what other conductive material was used as an insulator?
A: unanswerable

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In a career spanning more than four decades, Spielberg's films have covered many themes and genres. Spielberg's early science-fiction and adventure films were seen as archetypes of modern Hollywood blockbuster filmmaking. In later years, his films began addressing humanistic issues such as the Holocaust (in Schindler's List), the transatlantic slave trade (in Amistad), war (in Empire of the Sun, Saving Private Ryan, War Horse and Bridge of Spies) and terrorism (in Munich). His other films include Close Encounters of the Third Kind, the Indiana Jones film series, and A.I. Artificial Intelligence.
In what films did Spielberg address war?
A: Empire of the Sun, Saving Private Ryan, War Horse and Bridge of Spies

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The Lord Mayor's official residence is 3 Elliot Terrace, located on the Hoe. Once a home of Waldorf and Nancy Astor, it was given by Lady Astor to the City of Plymouth as an official residence for future Lord Mayors and is also used today for civic hospitality, as lodgings for visiting dignitaries and High Court judges and it is also available to hire for private events. The Civic Centre municipal office building in Armada Way became a listed building in June 2007 because of its quality and period features, but has become the centre of a controversy as the council planned for its demolition estimating that it could cost 40m to refurbish it, resulting in possible job losses.
At what street address is the Lord Mayor's residence located?
A: 3 Elliot Terrace

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Houston is recognized worldwide for its energy industryparticularly for oil and natural gasas well as for biomedical research and aeronautics. Renewable energy sourceswind and solarare also growing economic bases in the city. The Houston Ship Channel is also a large part of Houston's economic base. Because of these strengths, Houston is designated as a global city by the Globalization and World Cities Study Group and Network and global management consulting firm A.T. Kearney. The Houston area is the top U.S. market for exports, surpassing New York City in 2013, according to data released by the U.S. Department of Commerce's International Trade Administration. In 2012, the HoustonThe WoodlandsSugar Land area recorded $110.3 billion in merchandise exports. Petroleum products, chemicals, and oil and gas extraction equipment accounted for approximately two-thirds of the metropolitan area's exports last year. The Top 3 destinations for exports were Mexico, Canada, and Brazil.
In what did Houston pass New York City in 2013?
A:
market for exports