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單項(xiàng)選擇題

Overgreasing of ball bearings installed on pumps will result in （）.

A.smoother pump operation
B.overheating of the bearing
C.reduced corrosion in the bearing
D.increased pump capacity

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單項(xiàng)選擇題

The energy associated with molecules is known as （）.

A.kinetic energy
B.potential energy
C.mechanical energy
D.thermal energy

單項(xiàng)選擇題

“Flooding back” is a condition where the liquid refrigerant （）.

A.vaporizes in the condenser
B.reaches the compressor through the suction line
C.flashes in the liquid line
D.condenses in the receiver