To shut down a diesel engine after it exceeds the set maximum speed，which type of device listed should be used?（）

The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the（）

During the diesel engine running, the water level of F.W expansion tank should normally kept in the （） level of glass tube.

If separating effect is not good, which measure should be taken （）

If two A.C.generators are to be operated in parallel, the load is distributed evenly by（）

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）

Diesel engine air start system check valves are opened by （）

A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）

One of the reasons that cause oil flowed from sludge outlet of a self-cleaning separator is（）

The treatment of the fuel oils involves storage, heating, filtering and（）