单项选择题
A.lower than B.higher than C.below D.equal to
Large pipes or （） are fitted between the steam and wate...
单项选择题Large pipes or （） are fitted between the steam and water drums to ensure good natural circulation of water.
A.fire-tubes B.furnaces C.down-comers D.soot-blowers
（） system is arranged to ensure that water can be drawn...
单项选择题（） system is arranged to ensure that water can be drawn from any tank or the sea and discharged to any other tank or the sea as required to trim the vessel.
A.The domestic water B.Bilge water C.Oil transfer D.The ballast
（） connected to the moving tiller will bring the floati...
单项选择题（） connected to the moving tiller will bring the floating lever pivot and the lever into line at right angles to the screw shaft axis.
A.A cut-off lever B.A swivel block C.A cross-head D.A driving gear
