单项选择题
A.a change-over chest
B.a head tank
C.a emergency bilge pump
D.an air cooler
单项选择题 The control rod of a steering gear pump is attached at its outer end to ().
单项选择题 If a heavy sea strikes the rudder, the shock is transmitted through () to the rams, this cause a sudden increase in oil pressure in one of the cylinders.
单项选择题 Additional heat extraction from the exhaust gases can be effected by adding an () section to the unit in plants.