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

Which of the following is not an operation mode of AIS?（）

The force resulting from the earth’s rotation that causes winds to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere is called（）.

Shipboard Emergency Drills must be carried out at least（）on board cargo ship.

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

In the Northern hemisphere northerly winds may cause temperature（）.

A tide is called diurnal when（）.

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

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

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