The usual symptoms of cavitation in a centrifugal pump is （）.

The rate of heat transfer from a hot region to a cold region is affected most by the （）.

The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.

The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.

A pressure drop through the refrigerant liquid line may cause （）.

A salinity indicator is used to determine the （）.

An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of （）.

Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）

If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.

Which of the following statements is correct concerning heat transfer?（）