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.

At least two two-way VHF radiotelephone apparatus shall be provided on every cargo ship of（）tons gross tonnage and upwards but less than 500 tons gross tonnage.

What following is not among the function of SOLAS ships?（）

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

Monitoring is especially important in a highly automated system which is dependent on careful（）procedure and format.

The frequency（）the safety message will be transmitted shall be included in DSC safety call.

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

SafetyNet is an international service for the broadcast and automatic reception of MSI by means of direct-printing through（）system.

Radio beacon can be activated（）in case of distress.

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