单选题Oil pressure in the lubrication system is （） the static sea water head to ensure that sea water （） the stem-tube.Alower than；can lubricateBlower than；can coolChigher than；can enterDhigher than ；cannot enter
单选题
Oil pressure in the lubrication system is （） the static sea water head to ensure that sea water （） the stem-tube.
A
lower than；can lubricate
B
lower than；can cool
C
higher than；can enter
D
higher than ；cannot enter
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