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As in the Scheiner system, speeds were expressed in 'degrees'. Originally the sensitivity was written as a fraction with 'tenths' (for example "18/10° DIN"), where the resultant value 1.8 represented the relative base 10 logarithm of the speed. 'Tenths' were later abandoned with DIN 4512:1957-11, and the example above would be written as "18° DIN". The degree symbol was finally dropped with DIN 4512:1961-10. This revision also saw significant changes in the definition of film speeds in order to accommodate then-recent changes in the American ASA PH2.5-1960 standard, so that film speeds of black-and-white negative film effectively would become doubled, that is, a film previously marked as "18° DIN" would now be labeled as "21 DIN" without emulsion changes.
What happened to film speeds of black-and-white negative film?
A: would become doubled

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New York City is located on one of the world's largest natural harbors, and the boroughs of Manhattan and Staten Island are (primarily) coterminous with islands of the same names, while Queens and Brooklyn are located at the west end of the larger Long Island, and The Bronx is located at the southern tip of New York State's mainland. This situation of boroughs separated by water led to the development of an extensive infrastructure of bridges and tunnels. Nearly all of the city's major bridges and tunnels are notable, and several have broken or set records.
The borough of Staten Island is primarily located on what island?
A: Staten Island

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Until the death of Sigismund II Augustus, the last king of the Jagiellonian dynasty, monarchs could be elected from within only the royal family. However, starting from 1573, practically any Polish noble or foreigner of royal blood could become a Polish–Lithuanian monarch. Every newly elected king was supposed to sign two documents—the Pacta conventa ("agreed pacts")—a confirmation of the king's pre-election promises, and Henrican articles (artykuły henrykowskie, named after the first freely elected king, Henry of Valois). The latter document served as a virtual Polish constitution and contained the basic laws of the Commonwealth:
How many documents should the new elected king sign?
A: two documents

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Traditional English ale was made solely from fermented malt. The practice of adding hops to produce beer was introduced from the Netherlands in the early 15th century. Alehouses would each brew their own distinctive ale, but independent breweries began to appear in the late 17th century. By the end of the century almost all beer was brewed by commercial breweries.
What businesses were the dominant brewers of beer in England by the close of the 17th century?
A:
commercial breweries