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

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

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

A salinity indicator is used to determine the （）.

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

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

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

Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）

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

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