A. This is an interactive mode. B. Each character is repeated three times. C. Each character is transmitted twice. D. This mode is generally used to broadcast messages.
A. Three times. B. Three times at most. C. Twice. D. Six times.
Alert all ships in a limited sea area. B. Send the alert to all ships. C. Send the alert to the ships in the vicinity of a distress incident. D. Send the alert to several ships.
A. 4 digits. B. 5 digits. C. 7 digits. D. 9 digits.
A. Which is assisted B. That assists you C. When you assisted D. When being assisted
Area call. B. Distress call. C. Urgency call. DSC call.
A. when two stations communicate with each other B. in any radio system at any time C. when one ship sends messages to another D. for communication Among some stations
A. J3E. B. G2B. C. A1A. D. F1B or J2B.
A. constructs B. constructed C. has constructed D. was constructed
A. in major ocean regions and at regular times B. in case of distress C. at any time and from any location D. on fixed position and scheduled time
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