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

The company should establish and maintain procedures to control all documents and date which are relevant to（）.

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

Bales close to the deckhead should be covered to prevent（）.

The helm command PORT TWENTY means（）.

（）is the act of allocating space to containers on board of a container ship in the order of the discharge ports.

Fog is likely to occur when there is little difference between the dew point and the（）.

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

Manoeuvring information can not be obtained from（）.

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