The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.

All coast radio stations（）DSC installed for VHF and HF.

Ship-to-ship distress alerting should be conducted by（）.

Particular care should be（）in selecting CESs in areas where Ocean Regions overlap.

The vessel has stayed in port for seven days because she needs（）.

By using（）system a ship can send a distress message and know with certainty it will be received.

Stations in the United States of America are grouped by states arranged in the alphabetical order of their（）.

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.

Radiotelephony communication or radio telex communication or both will be carried out by terrestrial or satellite means,（）the equipment fitted on ship and the area in which the incident occurs.

（）by an ice-breaker, it is important to maintain a continuous listening watch on the appropriate VHF channel and to maintain a proper look-out for sound and visual signals.