A.sometimes
B.all times
C.never
D.partly
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A.to avoid mutual interference
B.to keep silence
C.owing to the time-share nature
D.to regulate transmitter power
A.from any INMARSAT satellite
B.via any appropriate Navtex and EGC station
C.via the satellite the MES is tracking
D.from any RCC and coast station
A.four
B.six
C.five
D.three
A.selective and can be suppressed by ships
B.mandatory and can not be suppressed by ships in the affected area
C.not very important so that ships don‟t require them
D.received by all ships wherever they are
A.all vessels
B.selected groups of ships
C.a particular ship
D.A, B, C are all right
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The frequency（）the safety message will be transmitted shall be included in DSC safety call.
The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.
Stations in the United States of America are grouped by states arranged in the alphabetical order of their（）.
We consider（）send a helicopter with medical facilities to the distress area.
For COSPAS-SARSAT system,（）usually transmit initial COSPAS-SARSAT alert.
COSPAS-SARSAT is intended to be used for（）.
International Navtex service means the coordinated broadcast and automatic reception on（）khz of maritime safety information by narrow-band direct-printing telegraphy using English language.
Distress traffic is the communication（）between the station in distress and the ships, aircraft, coast radio stations, coast earth stations and rescue centers participating in the rescue work.
Monitoring is especially important in a highly automated system which is dependent on careful（）procedure and format.
In case a ship is in emergency or distress in any of 4 areas, it is required to use the continuous（）alert.