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單項選擇題

The pressure range between the system cut in and cut out pressures in a refrigeration unit is known as（）

A.opposing operational drag
B.pressure distribution
C.differential
D.system purge

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單項選擇題

A fluid coil will （）large quantities of heat when it changes state from a liquid to a vapor.

A.release
B.absorb
C.develop
D.regenerate

單項選擇題

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）

A.Sub-cooled liquid
B.Sub-cooled vapor
C.Superheated vapor
D.Liquid

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