A.SOS sent three times
B.ten one-second dashes with a four-second interval between them
C.twelve four-second dashes with a one-second interval between them
D.twelve one-second dashes with a short interval between them
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A.1.5 and greater
B.1.25 and greater
C.1.0 and greater
D.0.5 and greater
A.hold anchor
B.leave anchor
C.let go anchor
D.weigh anchor
A.reduce the length of the cable
B.pay out more anchor cable
C.back the engines
D.swing the rudder several times to work the anchor into the bottom
A.Distress
B.Safety
C.All clear
D.Urgency
A.a ship is threatened by grave and imminent danger and requests immediate assistance
B.a calling station has an urgent message about the safety of a person
C.the message following the prefix will be about the safety of navigation
D.the message following is a meteorological warning
最新試題
To reduce mild fever the MOST useful drug is（）.
The radiotelegraph alarm signal is（）.
To predict the actual depth of water using the Tide Tables，the number obtained from the Tide Tables is（）.
What happens to the efficiency of an anchor when it is moved from sand to mud?（）
What form of ice is of land origin?（）
There is something wrong with our radar．All kinds of objects can’t be clearly（）within the definite range.
The transmission of messages respecting the dangers specified is free（）cost to the ships concerned.
The vessel was drifted off from her（）due to strong wind.
What is the normal length of anchor cable used to anchor a vessel?（）
In radiotelephone communications，the prefix PAN-PAN indicates that（）.