What does the abbreviation VHF stand for?（）

If you know that the vessel you are about to call on the VHF radio maintains a radio watch on both the working and the calling frequencies，which frequency should you call on? （）

All VHF marine band radios operate in the simplex mode，which means that（）.

（）both anchors.

Pilot Station，this is Chinese ship Jinsha（）.Over.

I am ready（）tow line.

The control of distress traffic is the responsibility of（）.

If it（）fine tomorrow，we shall start unloading.

A mark or place at which a vessel comes under obligatory entry，transit，or escort procedure is know as（）.

There is a drifting mine（）in position 21 degrees 31 minutes North 124 degrees 20 minutes East.