A.every six months
B.every year
C.every one and half year
D.every two years
您可能感興趣的試卷
你可能感興趣的試題
A.foam extinguishers
B.water spray equipment
C.dry powder extinguishers
D.soda-acid extinguishers
A.deprival of oxygen
B.removal of heat
C.spraying of water
D.injecting of soda-acid
A.deprival of oxygen
B.a water spray
C.soda-acid
D.foam
A.combustible material
B.ignition source
C.oxygen
D.A and B and C
A.Two derricks
B.A derrick and a crane
C.Two cranes
D.A crane and a winch
最新試題
A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）
As soon as a diesel engine has started, which of the listed engine operating parameters should be checked FIRST?（）
If separating effect is not good, which measure should be taken （）
（） is not installed on the main switchboar.
Under MARPOL Code the ship to which it applies has to carry （）
When does auxiliary burner of incinerator put into operation? （）Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish
Which of the listed governor characteristics will greatly affect the load sharing relationship between paralleled diesel generators?（）
Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）
To proceed to the assistance of a ship in distress is（）
One of the reasons that cause oil flowed from sludge outlet of a self-cleaning separator is（）