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 are lifts?, Context: Stage lifts and orchestra lifts are specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage. For example, Radio City Music Hall has four such elevators: an orchestra lift that covers a large area of the stage, and three smaller lifts near the rear of the stage. In this case, the orchestra lift is powerful enough to raise an entire orchestra, or an entire cast of performers (including live elephants) up to stage level from below. There's a barrel on the background of the image of the left which can be used as a scale to represent the size of the mechanism

A: specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage
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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: Which of the following is not an Arab nationalist term: Arab homeland, Arab singers or Arab nation?, Context: Nasser's street following was still too small to sustain his plans for reform and to secure him in office. To promote himself and the Liberation Rally, he gave speeches in a cross-country tour, and imposed controls over the country's press by decreeing that all publications had to be approved by the party to prevent "sedition". Both Umm Kulthum and Abdel Halim Hafez, the leading Arab singers of the era, performed songs praising Nasser's nationalism. Others produced plays denigrating his political opponents. According to his associates, Nasser orchestrated the campaign himself. Arab nationalist terms such "Arab homeland" and "Arab nation" frequently began appearing in his speeches in 195455, whereas prior he would refer to the Arab "peoples" or the "Arab region". In January 1955, the RCC appointed him as their president, pending national elections.

A:
Arab singers
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