Vessels shall be deemed to be in sight of one another only when one（）from the other.

单项选择题Vessel underway means that a vessel is（）.

A.on the way
B.at anchor
C.made fast to a terminal
D.moving against water

单项选择题Vessel constrained by her draught is（）.

A.a non-power driven vessel
B.a sailing vessel
C.a power driven vessel
D.a power driven vessel or a non-power driven vessel

单项选择题Underway vessels shall at all time maintain a proper look-out（）.

A.by sight and hearing only
B.by all available means besides sight and hearing
C.by all available means except sight and hearing
D.by none of above means

单项选择题Under International Rules（）.

A.all vessels must carry an after range light
B.vessels less than 50 meters in length need not carry an after range light
C.vessels stopped dead in the water should turn off their range lights
D.vessels over 20 meters in length must carry both range lights from sunset to sunrise

单项选择题The wind is ESE，and a sailing vessel is steering NW. Which fog signal should she sound?（）

A.One blast at one-minute intervals
B.One blast at two-minute intervals
C.Two blasts at one-minute intervals
D.One prolonged and two short blasts at two-minute intervals