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

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

（）is halfway between the forward and after perpendiculars and is reference point for vessel construction.

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

ECDIS must be able to perform all of the following EXCEPT（）.

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

Which wind results from a land mass cooling more quickly at night than an adjacent water area?（）

The loading of the ship must be done in accordance with（）.

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（）.