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单选题
（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.
A
Large crosshead type；crossheads
B
High speed；the cylinders
C
Large crosshead type；the cylinders
D
Four-stroke；pistons and cylinders
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更多 “单选题（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.A Large crosshead type；crossheadsB High speed；the cylindersC Large crosshead type；the cylindersD Four-stroke；pistons and cylinders” 相关考题
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单选题（） providing lubricating films, oil used in marine diesel engines have to remove heat from oil cooled piston.A
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ExceptD
In addition to
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cetane numberB
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the power strokeB
the compression strokeC
low load operation onlyD
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