A.velocity of the currentB.bottom characteristicsC.dept……

单项选择题A deadhead is a(n)（）.

A.tree or log awash in a nearly vertical position
B.crew member who refuses to work
C.upstream end of a land wall
D.buoy that is adrift

单项选择题A barometer showing falling pressure indicates the approach of a（）.

A.high pressure system
B.low pressure system
C.high dew point
D.low dew point

单项选择题（）the canal transit，the radar was operating.

A.At
B.In
C.During
D.With

单项选择题（）should be used during the poor visibility if the radar’s screen shows heavy sea returns.

A.Gain Control
B.Brilliant Control
C.Anti-clutter Sea Control
D.Sweep Intercept

单项选择题（）is on the panel of radar.

A.KEYLOCK
B.REPEATER
C.STATIC INVERTER
D.ANTI-CLUTTER-SEA