In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Q: What needs consistency?, Context: The simplest valve gears give events of fixed length during the engine cycle and often make the engine rotate in only one direction. Most however have a reversing mechanism which additionally can provide means for saving steam as speed and momentum are gained by gradually "shortening the cutoff" or rather, shortening the admission event; this in turn proportionately lengthens the expansion period. However, as one and the same valve usually controls both steam flows, a short cutoff at admission adversely affects the exhaust and compression periods which should ideally always be kept fairly constant; if the exhaust event is too brief, the totality of the exhaust steam cannot evacuate the cylinder, choking it and giving excessive compression ("kick back").[citation needed]

A: exhaust and compression periods
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Q: What styles influenced the styles used in the region?, Context: Increasing military and cultural contacts with the Muslim world, including the Norman conquest of Islamic Sicily in 1090, the Crusades, beginning 1096, and the Islamic presence in Spain, may have influenced Medieval Europe's adoption of the pointed arch, although this hypothesis remains controversial. Certainly, in those parts of the Western Mediterranean subject to Islamic control or influence, rich regional variants arose, fusing Romanesque and later Gothic traditions with Islamic decorative forms, as seen, for example, in Monreale and Cefalù Cathedrals, the Alcázar of Seville, and Teruel Cathedral.

A: Gothic traditions with Islamic decorative forms
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Q: What happened after the act?, Context: Chris Daughtry's performance of Fuel's "Hemorrhage (In My Hands)" on the show was widely praised and led to an invitation to join the band as Fuel's new lead singer, an invitation he declined. His performance of Live's version of "I Walk the Line" was well received by the judges but later criticized in some quarters for not crediting the arrangement to Live. He was eliminated at the top four in a shocking result.

A:
led to an invitation to join the band as Fuel's new lead singer, an invitation he declined
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