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

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

If the beacon is mounted at a wrong place, it may（）by sea water, chemicals, exhaust and vibrations.

As each MSI message will have a unique identity, the printing of messages already received correctly is（）.

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

For COSPAS-SARSAT system,（）usually transmit initial COSPAS-SARSAT alert.

COSPAS-SARSAT is intended to be used for（）.

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

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.

Every lifeboat which is fitted with a fixed two-way（）radiotelephone apparatus with an antenna which is separately mounted shall be provided with arrangements for sitting and securing the antenna effectively in its operating position.