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單項(xiàng)選擇題

The color of the flame on a halide torch without any refrigerant present is （）.

A.blue
B.green
C.orange
D.purple

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單項(xiàng)選擇題

The color of the flame on a halide torch without any refrigerant present is （）.

A.blue
B.green
C.orange
D.purple

單項(xiàng)選擇題

If a refrigeration compressor is running continuously without lowering temperature as normal in the refrigerator, the trouble may be （）.

A.excessive condenser cooling water
B.warm food in the refrigerator
C.a shortage of refrigerant
D.s shortage of compressor oil

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