Problem: Labour Party (UK):

On 1 March 2014, at a special conference the party reformed internal Labour election procedures, including replacing the electoral college system for selecting new leaders with a "one member, one vote" system following the recommendation of a review by former general-secretary Ray Collins. Mass membership would be encouraged by allowing "registered supporters" to join at a low cost, as well as full membership. Members from the trade unions would also have to explicitly "opt in" rather than "opt out" of paying a political levy to Labour.

Who had to opt in to paying a political levy to the Conservatives?
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A: unanswerable

Problem: Qing dynasty:

China also began suffering from mounting overpopulation during this period. Population growth was stagnant for the first half of the 17th century due to civil wars and epidemics, but prosperity and internal stability gradually reversed this trend. The introduction of new crops from the Americas such as the potato and peanut allowed an improved food supply as well, so that the total population of China during the 18th century ballooned from 100 million to 300 million people. Soon all available farmland was used up, forcing peasants to work ever-smaller and more intensely worked plots. The Qianlong Emperor once bemoaned the country's situation by remarking "The population continues to grow, but the land does not." The only remaining part of the empire that had arable farmland was Manchuria, where the provinces of Jilin and Heilongjiang had been walled off as a Manchu homeland. The emperor decreed for the first time that Han Chinese civilians were forbidden to settle. Mongols were forbidden by the Qing from crossing the borders of their banners, even into other Mongol Banners and from crossing into neidi (the Han Chinese 18 provinces) and were given serious punishments if they did in order to keep the Mongols divided against each other to benefit the Qing.

How many people lived in China at the end of the 20th century?
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A: 300 million

Problem: New Delhi:

The foundation stone of the city was laid by George V, Emperor of India during the Delhi Durbar of 1911. It was designed by British architects, Sir Edwin Lutyens and Sir Herbert Baker. The new capital was inaugurated on 13 February 1931, by India's Viceroy Lord Irwin.

On what date was New Delhi inaugurated?
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A: 13 February 1931

Problem: Alps:

Human interference has nearly exterminated the trees in many areas, and, except for the beech forests of the Austrian Alps, forests of deciduous trees are rarely found after the extreme deforestation between the 17th and 19th centuries. The vegetation has changed since the second half of the 20th century, as the high alpine meadows cease to be harvested for hay or used for grazing which eventually might result in a regrowth of forest. In some areas the modern practice of building ski runs by mechanical means has destroyed the underlying tundra from which the plant life cannot recover during the non-skiing months, whereas areas that still practice a natural piste type of ski slope building preserve the fragile underlayers.

What has changed since the second half of the 20th century?
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A:
The vegetation