问题：
[单选] Compressed air is supplied by air compression to （）.
the air receivers。the starting valves。the cylinder covers。the distributor。
问题：
[单选] Compressed air is used on board ship （）.
for starting diesel engines。in pneumatic control system。in pneumatic tools。All the above are true。
问题：
[单选] Cooling of engine is achieved by circulation a cooling liquid around internal passages within the （）.
boiler。heater。engine。cooler。
问题：
[单选] Cracks in cylinder and cylinder covers may （） from unequal heating.
make。cause。result。produce。
问题：
[单选] Crankshafts of medium speed engines are （） from a single piece of steel.
unusually solid welded。never be solid forged。almost invariably solid forged。almost invariably be welded。
问题：
[单选] Cylinder liner cooling is often referred to as （）.
piston cooling。sleeve cooling。central cooling。jacket cooling。
问题：
[单选] Cylinders of marine diesel engines are normally cooled by （）.
sea water。fine mineral oil。sanitary water。fresh water。
问题：
[单选] Diesel engines are started by supplying （） into the cylinders in the appropriate sequence for the required direction.
cooling water。compressing air。compressed air。cylinder oil。
问题：
[单选] Diesel engines are started by supplying （） into the cylinders in the appropriate sequence for the required direction.
fuel oil。diesel oil。compressed air。jacket water。
问题：
[单选] Diesel oil may be used to cool （） of a diesel engine.
cylinders。exhaust valves。pistons。fuel valve。
