Problem: Wood:

In buildings made of other materials, wood will still be found as a supporting material, especially in roof construction, in interior doors and their frames, and as exterior cladding.

What crucial part of a house is often constructed from wood?
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A: roof


Problem: Pain:

The most reliable method for assessing pain in most humans is by asking a question: a person may report pain that cannot be detected by any known physiological measure. However, like infants (Latin infans meaning "unable to speak"), animals cannot answer questions about whether they feel pain; thus the defining criterion for pain in humans cannot be applied to them. Philosophers and scientists have responded to this difficulty in a variety of ways. René Descartes for example argued that animals lack consciousness and therefore do not experience pain and suffering in the way that humans do. Bernard Rollin of Colorado State University, the principal author of two U.S. federal laws regulating pain relief for animals, writes that researchers remained unsure into the 1980s as to whether animals experience pain, and that veterinarians trained in the U.S. before 1989 were simply taught to ignore animal pain. In his interactions with scientists and other veterinarians, he was regularly asked to "prove" that animals are conscious, and to provide "scientifically acceptable" grounds for claiming that they feel pain. Carbone writes that the view that animals feel pain differently is now a minority view. Academic reviews of the topic are more equivocal, noting that although the argument that animals have at least simple conscious thoughts and feelings has strong support, some critics continue to question how reliably animal mental states can be determined. The ability of invertebrate species of animals, such as insects, to feel pain and suffering is also unclear.

What is the most reliable method of learning about pain in a human?
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A: asking a question


Problem: BeiDou Navigation Satellite System:

In February 2007, the fourth and last satellite of the BeiDou-1 system, BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.

What happened to the BeiDou-1D satellite that needed to be repaired?
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A: a control system malfunction


Problem: British Empire:

In 1951, the Conservative Party returned to power in Britain, under the leadership of Winston Churchill. Churchill and the Conservatives believed that Britain's position as a world power relied on the continued existence of the empire, with the base at the Suez Canal allowing Britain to maintain its pre-eminent position in the Middle East in spite of the loss of India. However, Churchill could not ignore Gamal Abdul Nasser's new revolutionary government of Egypt that had taken power in 1952, and the following year it was agreed that British troops would withdraw from the Suez Canal zone and that Sudan would be granted self-determination by 1955, with independence to follow. Sudan was granted independence on 1 January 1956.

When did Sudan receive independence?
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A:
1 January 1956