Problem: Geography of the United States:

The Intermontane Plateaus come to an end at the Cascade Range and the Sierra Nevada. The Cascades consist of largely intermittent, volcanic mountains, many rising prominently from the surrounding landscape. The Sierra Nevada, further south, is a high, rugged, and dense mountain range. It contains the highest point in the contiguous 48 states, Mount Whitney (14,505 ft or 4,421 m) It is located at the boundary between California's Inyo and Tulare counties, just 84.6 mi or 136.2 km west-northwest of the lowest point in North America at the Badwater Basin in Death Valley National Park at 279 ft or 85 m below sea level.

The Cascades consist largely of overlapping what?
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A: unanswerable

Problem: Hard rock:

Hard rock developed into a major form of popular music in the 1970s, with bands such as Led Zeppelin, The Who, Deep Purple, Aerosmith, AC/DC and Van Halen. During the 1980s, some hard rock bands moved away from their hard rock roots and more towards pop rock, while others began to return to a hard rock sound. Established bands made a comeback in the mid-1980s and it reached a commercial peak in the 1980s, with glam metal bands like Bon Jovi and Def Leppard and the rawer sounds of Guns N' Roses, which followed up with great success in the later part of that decade. Hard rock began losing popularity with the commercial success of grunge and later Britpop in the 1990s.

When did hard rock replace grunge and Britpop?
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A: unanswerable

Problem: Paris:

The security of Paris is mainly the responsibility of the Prefecture of Police of Paris, a subdivision of the Ministry of the Interior of France. It supervises the units of the National Police who patrol the city and the three neighbouring departments. It is also responsible for providing emergency services, including the Paris Fire Brigade. Its headquarters is on Place Louis Lepine on the Ile de la Cite. There are 30,200 officers under the prefecture, and a fleet of more than 6,000 vehicles, including police cars, motorcycles, fire trucks, boats and helicopters. In addition to traditional police duties, the local police monitors the number of discount sales held by large stores (no more than two a year are allowed) and verify that, during summer holidays, at least one bakery is open in every neighbourhood. The national police has its own special unit for riot control and crowd control and security of public buildings, called the Compagnies Republicaines de Securite (CRS), a unit formed in 1944 right after the liberation of France. Vans of CRS agents are frequently seen in the centre of the city when there are demonstrations and public events.

How many officers are in the Prefecture of Police of Paris?
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A: 30,200

Problem: Late Middle Ages:

Around 13001350 the Medieval Warm Period gave way to the Little Ice Age. The colder climate resulted in agricultural crises, the first of which is known as the Great Famine of 1315-1317. The demographic consequences of this famine, however, were not as severe as the plagues that occurred later in the century, particularly the Black Death. Estimates of the death rate caused by this epidemic range from one third to as much as sixty percent. By around 1420, the accumulated effect of recurring plagues and famines had reduced the population of Europe to perhaps no more than a third of what it was a century earlier. The effects of natural disasters were exacerbated by armed conflicts; this was particularly the case in France during the Hundred Years' War.

When did the Medieval Warm Period start?
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A:
unanswerable