Multiple fire pumps may be used for other purposes provided that one pump is（）.

单项选择题Large volumes of carbon dioxide are safe and effective for fighting fires in enclosed spaces，such as in a pumproom，provided that the（）.

A.persons in the space wear gas masks
B.persons in the space wear damp cloths over their mouths and nostrils
C.ventilation system is secured and all persons leave the space
D.ventilation system is kept operating

单项选择题Inflatable liferafts are less maneuverable than lifeboats due to their（）.

A.shape
B.shallow draft
C.large sail area
D.All of the above

单项选择题In which situation could a vessel most easily capsize?（）

A.Running into head seas
B.Running in the trough
C.Running with following seas
D.Anchored with your bow into the seas

单项选择题In heavy seas you decide to heave to. The lifeboat should be（）.

A.brought to a position with the stern into the seas
B.allowed to take its own head
C.brought to lay in the trough
D.brought bow into the seas

单项选择题In heavy seas the helmsman should steer the motor lifeboat（）.

A.into the seas
B.broadside to the seas
C.in the same direction as the seas
D.in a series of figure-eights