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

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

A salinity indicator is used to determine the （）.

An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.

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

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

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 （）.

A gradual decrease in the discharge pressure of an operating hydraulic pump can 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 （）.