Here is a question about this article: Solar distillation can be used to make saline or brackish water potable. The first recorded instance of this was by 16th-century Arab alchemists. A large-scale solar distillation project was first constructed in 1872 in the Chilean mining town of Las Salinas. The plant, which had solar collection area of 4,700 m2 (51,000 sq ft), could produce up to 22,700 L (5,000 imp gal; 6,000 US gal) per day and operate for 40 years. Individual still designs include single-slope, double-slope (or greenhouse type), vertical, conical, inverted absorber, multi-wick, and multiple effect. These stills can operate in passive, active, or hybrid modes. Double-slope stills are the most economical for decentralized domestic purposes, while active multiple effect units are more suitable for large-scale applications.
What is the answer to this question: What is used to make saline or brackish water drinkable?
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So... Solar distillation

Here is a question about this article: The term "classical music" did not appear until the early 19th century, in an attempt to distinctly canonize the period from Johann Sebastian Bach to Beethoven as a golden age. The earliest reference to "classical music" recorded by the Oxford English Dictionary is from about 1836.
What is the answer to this question: What year is the earliest reference to 'classical music'?
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So... 1836

Here is a question about this article: Tobacco was one of the first major industries to develop after the Civil War. Many farmers grew some tobacco, and the invention of the cigarette made the product especially popular. Winston-Salem is the birthplace of R. J. Reynolds Tobacco Company (RJR), founded by R. J. Reynolds in 1874 as one of 16 tobacco companies in the town. By 1914 it was selling 425 million packs of Camels a year. Today it is the second-largest tobacco company in the U.S. (behind Altria Group). RJR is an indirect wholly owned subsidiary of Reynolds American Inc., which in turn is 42% owned by British American Tobacco.
What is the answer to this question: The invention of cigarettes made what popular?
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So...
Tobacco