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單項選擇題The lube oil in the bearings is drawn from a （）, usually located in the bedplate.

A.tank
B.sump
C.vessel
D.bottle

1.單項選擇題The lowest ring of a piston is （）.

A.a coil spring
B.a sealing ring
C.an oil distributor ring
D.main seal ring

2.單項選擇題The lower end of each piston rod is reduced in diameter to fit a bore in （）.

A.the crosshead
B.the journals of the crosshead
C.the crosshead shoes
D.the guides

3.單項選擇題The lower end of each piston rod is reduced in diameter to fit a bore in （）, this being secured to the piston rod by a nut.

A.the crank-web
B.the connecting rod
C.the main bearing
D.the cross-head

4.單項選擇題The lower end of each piston rod is reduced in diameter to fit a bore in the cross-head, this being secured to the piston rod by （）.

A.a bolt
B.a cap
C.a disc
D.a nut

5.單項選擇題The lower end of each piston rod is reduced in diameter to fit a bore in the （）, this being secured to the piston rod by a nut.

A.piston gudgeon pin
B.piston skirt
C.cross-head
D.cross-head pin