Problem: Alexander Graham Bell:

Alexander Graham Bell was ranked 57th among the 100 Greatest Britons (2002) in an official BBC nationwide poll, and among the Top Ten Greatest Canadians (2004), and the 100 Greatest Americans (2005). In 2006 Bell was also named as one of the 10 greatest Scottish scientists in history after having been listed in the National Library of Scotland's 'Scottish Science Hall of Fame'. Bell's name is still widely known and used as part of the names of dozens of educational institutes, corporate namesakes, street and place names around the world.

In 2002, where did Bell place in a list of the Greatest Britons?
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A: 57th

Problem: Anti-aircraft warfare:

The ammunition and shells fired by these weapons are usually fitted with different types of fuses (barometric, time-delay, or proximity) to explode close to the airborne target, releasing a shower of fast metal fragments. For shorter-range work, a lighter weapon with a higher rate of fire is required, to increase a hit probability on a fast airborne target. Weapons between 20 mm and 40 mm caliber have been widely used in this role. Smaller weapons, typically .50 caliber or even 8 mm rifle caliber guns have been used in the smallest mounts.

What are two types of fuses used for shells?
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A: barometric, time-delay, or proximity

Problem: Chihuahua (state):

But the peace in the state did not last long, the elections of 1875 caused new hostilities. Angel Trias led a new movement against the government in June 1875 and maintained control over the government until September 18, 1875 when Donato Guerra the orchestrator of the Revolution of the North was captured. Donato Guerra was assassinated in a suburb of Chihuahua City where he was incarcerated for conspiring with Angel Trias. During October 1875 several locations were controlled by rebel forces, but the government finally regained control on November 25, 1875.

With whom was he said to have conspired?
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A: Angel Trias

Problem: Bras%C3%ADlia:

The Cathedral of Brasilia in the capital of the Federative Republic of Brazil, is an expression of the architect Oscar Niemeyer. This concrete-framed hyperboloid structure, seems with its glass roof reaching up, open, to the heavens. On 31 May 1970, the Cathedral's structure was finished, and only the 70 m (229.66 ft) diameter of the circular area were visible. Niemeyer's project of Cathedral of Brasilia is based in the hyperboloid of revolution which sections are asymmetric. The hyperboloid structure itself is a result of 16 identical assembled concrete columns. These columns, having hyperbolic section and weighing 90 t, represent two hands moving upwards to heaven. The Cathedral was dedicated on 31 May 1970.

How much does the glass weigh?
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A:
unanswerable