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单选题
Crankshafts of medium speed engines are （） from a single piece of steel.
A
unusually solid welded
B
never be solid forged
C
almost invariably solid forged
D
almost invariably be welded
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单选题Crankshafts of medium speed engines are （） from a single piece of steel.A
unusually solid weldedB
never be solid forgedC
almost invariably solid forgedD
almost invariably be welded
考题
单选题The crankshafts of medium speed engines are almost invariably solid （） from a single piece of steel.A
forgedB
castC
madeD
shrunk
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单选题Although the crankshafts of medium diesel engines appear to be robust, they rely on the support of （） to develop their full strength.A
the piston rodsB
the crank throwsC
the thrust bearingsD
the main bearings
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单选题What best describes processing delay？（）A
the time required from receipt of the incoming frame， until the frame/packet has been queued for transmissionB
the time taken for a single packet to traverse the physical medium from one end to the otherC
the time taken to place a frame on the physical medium for transportD
the time spent for a packet to reside in the output queue of a router
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单选题Prior to starting most medium-speed propulsion diesel engines, which of the procedures listed should be observed?（）A
The expansion tank should be topped offB
The thermostatic water regulating valves should be manually openedC
The fuel filters should be changedD
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单选题Pistons of marine medium speed diesel engines may be made of （） in order to keep the weight down for balancing purpose at high speed.A
leadB
forged steelC
alloy steelD
aluminum alloy
考题
单选题Most medium and slow speed diesels are started by what medium?（）A
Electric starting motorsB
HydraulicsC
Compressed airD
Ether
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