单选题The current flowing first in one direction and then in another is called（） current.A an alternatingB a rushC a directD an exciting

For full information regarding the current circulation of the Indian Ocean，______ Sailing Direction，Current Atlas，etc．

A.watch

B.look for

C.see

D.regard

Which statement concerning current is TRUE ________．

A.Current can be determined by measuring the direction and distance between simultaneous EP and DR positions

B.The drift of the current should be averaged out on a one hour basis

C.After the current is determined，it should not be used for further plotting because it is an unknown variable

D.The distance between a simultaneous DR position and fix is equal to the drift of the current

The navigational term Set of current means ______.

A.velocity of current in knots

B.direction from which the current flows

C.estimated current

D.direction toward which the current flows

FLOATING ， CAUSED BY WINDS AND CURRENT WITH A DETERMINABLE DIRECTION defines______．

A.Floating

B.Sailing

C.Running into danger

D.Drifting

You are anchoring in a river where the current is from one direction only．The best way to lay out two anchors is to have them ______．

A.Directly in line with the bow

B.Side by side，with their lines on the port and starboard side

C.So that their lines form an angle

D.On top of one another

A ______ is one which affects almost the entire load virtually instantaneously．

A.mass explosion

B.projection

C.fire

D.flowing

Set of current is ________ ．

A.its velocity in knots

B.direction from which it flows

C.estimated current

D.direction toward which it flows