An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.

Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）

The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest in which of the flow designs listed?（）

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

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

Thermostatic expansion valves can be adjusted for （）.

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

Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.

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