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

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

Manoeuvring information can not be obtained from（）.

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

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

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

The mean draft of a ship is the draft（）.

What is a CORRECT reply to a pilot’s request, How’s your heading?（）

When steering by autopilot,how often should the steering be checked?（）

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（）.