单项选择题
A.parallel bearings B.long-range bearings C.short-range bearings D.cross bearings
Vessels in port may use（）for receiving typhoon warnings...
单项选择题Vessels in port may use（）for receiving typhoon warnings during the typhoon season.
A.their transmitters B.their receivers C.their radars D.their lorans
We’ll see（）the compasses are in good condition.A.ifB.ho...
单项选择题We’ll see（）the compasses are in good condition.
A.if B.how C.when D.where
More exact assessment of visibility when（）is used to de...
单项选择题More exact assessment of visibility when（）is used to determine the range of vessel or other objects in the vicinity.
A.radar B.omega C.satellite navigator D.DF
