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?（）

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

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

Which of the following statements is correct concerning heat transfer?（）

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

On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.

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

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

If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.