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單項(xiàng)選擇題

The evaporating pressure in R22 vapor compression refrigeration plant should be （） atmospheric.

A.below
B.above
C.equal to
D.much larger than

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單項(xiàng)選擇題

The primary task of the compressed air system is to deliver the starting air necessary for （）

A.starting the ME
B.starting the emergency electric alternator
C.driving the main turbine
D.driving the turbocharger

單項(xiàng)選擇題

The starting air bottle should be pumped up to maximum pressure by the （） before start of the engine.

A.air compressor
B.refrigeration compressor
C.vacuum pump
D.purifier

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