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

Thermostatic expansion valves can be adjusted for （）.

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

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

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

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

Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.

Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）

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

When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.