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單項(xiàng)選擇題

A （） boiler is an auxiliary boiler sometimes included in a steamships installation for supplying steam to auxiliaries in port.

A.monkey
B.donkey
C.waste heat
D.main

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單項(xiàng)選擇題

Between the steam dram and the smaller water dram below, large numbers of smaller diameter （） tubes are fitted.

A.fire
B.water wall
C.generating
D.down comer

單項(xiàng)選擇題

The safety valve should be （） in the presence of C/E and Surveyor.

A.tightened up
B.sealed up
C.opened up
D.unscrewed