单项选择题
A.high pressure system B.low pressure system C.high dew point D.low dew point
（）the canal transit，the radar was operating.A.AtB.InC.D...
单项选择题（）the canal transit，the radar was operating.
A.At B.In C.During D.With
（）should be used during the poor visibility if the rada...
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
（）is on the panel of radar.A.KEYLOCKB.REPEATERC.STATIC ...
单项选择题（）is on the panel of radar.
A.KEYLOCK B.REPEATER C.STATIC INVERTER D.ANTI-CLUTTER-SEA
