The frequency 2,174.5 kHz in NBDP service is used for ______.

Regarding sending an urgency message to "all ships" via NBDP terminal, which of the followings is correct?

NBDP equipment is a full, partial or alternate carriage requirement under GMDSS for vessels operating in the sea area(s) ______.

______ is not a NBDP frequency.

The group of keystrokes or characters of followings ______ will follow most commands in an ARQ communications.

Regarding a NBDP call to shore station SHAI CN, whose selective calling number is 2010, which sequence of characters or means would be used?

Weather broadcasts and vessel traffic lists are normally transmitted by shore stations in mode ______.

In NBDP service, the ______ mode would be selected to receive weather broadcasts from high seas shore stations.

You can receive traffic lists at sea via ______ mode.

The group keystrokes or characters in choice ______ is sent as part of ARQ communications to signal the end of the text.

What is ARQ?

Once ARQ communications with the coast radio station has been established, what will happen?

How can you determine the best frequency to choose for a NBDP transmission to a shore station?

If you intend to send a message to subscribers ashore directly by NBDP, you will use the instruction ______.

The usual purpose of pairing frequencies in duplex communications is ______.