The general purpose of a heat exchanger is to （）.

The major source of chemical contaminants in hydraulic fluid is （）.

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

A grease gun is generally used to lubricate a （）.

If the head pressure of a reciprocating refrigeration compressor is excessive, （）.

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 （）.

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

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

If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump （）.

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