According to the relevant regulation, lifeboat should be powered by（）.

When the wave period and the apparent rolling period are the same（）.

Full details of all lights and fog signals are shown on（）.

The ISM code is part of（）.

Which of the following is not a form of precipitation?（）

A tide is called diurnal when（）.

Despite the rising importance and great convenience of the gyrocompass,the magnetic compass still retain its importance because of its（）.

Before any loading takes place any signs of the previous cargo should do（）.

It is dangerous for vessels without the operational radar（）the estuary.

How long are you prohibited to consume alcohol prior to serving as a member of a watch?（）