单项选择题
A.all fishing vessels over 39 feet in length B.sail-propelled fishing vessels C.all fishing vessels of less than 200 GT D.wooden hull fishing vessels with a poor radar echo
Radar makes it possible and much safer for us to sail（）...
单项选择题Radar makes it possible and much safer for us to sail（）.
A.in dense fog B.in boisterous weather C.in the open sea D.in rivers
Radar beacons are transmitters designed to produce a（）o...
单项选择题Radar beacons are transmitters designed to produce a（）on the screens of ship’s radar sets.
A.incorrect image B.distinctive image C.pictorial image D.pictographic image
Proper use shall be made（）radar equipment.A.withB.toC.f...
单项选择题Proper use shall be made（）radar equipment.
A.with B.to C.for D.of
