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

The dew point temperature is（）.

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

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

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

（）is on the panel of radar.

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

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

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（）.