The output volume of a positive fixed displacement pump can be changed only by （）.

On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.

Thermostatic expansion valves can be adjusted for （）.

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

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

Low compressor head pressure in a refrigeration system can be caused by（）.

Which of the listed pumps is NOT a positive displacement pump?（）

The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.

If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.

If you are given the job of adding hydraulic fluid to a mooring winch, and are not certain as to the type of fluid to use, you should （）.