Problem: Beer:

Drinking chilled beer began with the development of artificial refrigeration and by the 1870s, was spread in those countries that concentrated on brewing pale lager. Chilling beer makes it more refreshing, though below 15.5 °C the chilling starts to reduce taste awareness and reduces it significantly below 10 °C (50 °F). Beer served unchilled—either cool or at room temperature, reveal more of their flavours. Cask Marque, a non-profit UK beer organisation, has set a temperature standard range of 12°–14 °C (53°–57 °F) for cask ales to be served.

What began in the 1780s?
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A: unanswerable


Problem: Sony Music Entertainment:

In 1929, ARC was founded through a merger of several smaller record companies, which, ultimately, transformed into one enterprise known as SME. In the depths of the Great Depression, the Columbia Phonograph Company (founded in 1888) in the U.S. (including its Okeh Records subsidiary) was acquired by ARC in 1934.

The Columbia Photography Company was founded in what year?
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A: unanswerable


Problem: Bird migration:

Long distance migrants are believed to disperse as young birds and form attachments to potential breeding sites and to favourite wintering sites. Once the site attachment is made they show high site-fidelity, visiting the same wintering sites year after year.

Where do migrating birds visit?
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A: the same wintering sites year after year


Problem: Josip Broz Tito:

On 26 June 1950, the National Assembly supported a crucial bill written by Milovan Đilas and Tito about "self-management" (samoupravljanje): a type of cooperative independent socialist experiment that introduced profit sharing and workplace democracy in previously state-run enterprises which then became the direct social ownership of the employees. On 13 January 1953, they established that the law on self-management was the basis of the entire social order in Yugoslavia. Tito also succeeded Ivan Ribar as the President of Yugoslavia on 14 January 1953. After Stalin's death Tito rejected the USSR's invitation for a visit to discuss normalization of relations between two nations. Nikita Khrushchev and Nikolai Bulganin visited Tito in Belgrade in 1955 and apologized for wrongdoings by Stalin's administration. Tito visited the USSR in 1956, which signaled to the world that animosity between Yugoslavia and USSR was easing. However, the relationship between the USSR and Yugoslavia would reach another low in the late 1960s. Commenting on the crisis, Tito concluded that:

Whose invitation did Tito reject after Stalin's death?
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A:
USSR