A.AnemometerB.FathometerC.BarometerD.ThermometerWhich i……

单项选择题Which effect does speed through the water have on a vessel which is underway in shallow water （）.

A.A decrease in the speed results in a decrease in steering response and maneuverability
B.An increase in speed results in the stern sucking down lower than the Bow
C.An increase in speed results in the vessel rising on an even plane
D.A decrease in speed results in the vessel sucking down on an even plane

单项选择题When liquid is free to move transversely in a tank，the effect is called（）.

A.free communication
B.free density
C.free surface
D.negative GM

单项选择题The term of Landfall means（）.

A.Land first sighted when vessel approaching from seaward
B.Land last sighted when vessel leaving from a port
C.In sight of one another when vessel underway
D.In sight of an island during a ship on her voyage

单项选择题Preferred channel marks are colored with（）．

A.black and green bands
B.red and green bands
C.red and yellow bands
D.yellow and green bands

单项选择题Preferred channel marks are aids to navigation which all following marks other than（）．

A.channel junctions
B.bifurcations
C.fishing traps
D.wrecks or obstructions