The description Racon beside an illustration on a chart would mean a（）.

单项选择题The correct method of switching off a marine radar is to turn power switch to（）position first，then to（）position.

A.off／standby
B.standby／off
C.standby／close
D.close／standby

单项选择题The common way to obtain your ship’s position is（）.

A.keeping a close watch and lookout
B.taking a radar range and bearing
C.observing a radar target and listening to signals
D.keeping a well clear caution

单项选择题The closest point of approach (CPA) of a contact on a relative motion radar may be determined（）.

A.immediately when the contact is noted on radar
B.only if the radar scope is watched constantly
C.after the contact has been marked at least twice
D.by an occasional glance at the radar

单项选择题The articulated light is superior to other types of buoys because（）.

A.the radar reflectors reflect better signals
B.fog horn signals travel farther to sea
C.it is equipped with strobe lights
D.it has a reduced watch circle

单项选择题The ARPA may swap targets when automatically tracking if two targets（）.

A.are tracked on reciprocal bearings
B.are tracked at the same range
C.are tracked on the same bearing
D.pass close together