After being launched from a vessel，totally enclosed survival craft which have been afloat over a long period require（）.

Aboard a survival craft，ether can be used to（）.

What is the use of the books of Admiralty List of Lights and Fog Signals? Their use is to （）.

To predict the actual depth of water using the Tide Tables，the number obtained from the Tide Tables is（）.

Mean high water is the average height of（）.

Lines drawn through points on the Earth having the same atmospheric pressure are known as （）.

A vessel in distress should send by radio telephone the two tone alarm signal followed immediately by the（）.

An inflatable liferaft is hand-launched by（）.

The latest known details of lights are given in（）.

The daily predictions of the times and heights of high and low water for a selection of Standard Ports are given in（）.