A.the radar reflectors reflect better signalsB.fog horn……

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

单项选择题The 3-cm radar as compared to a 10-cm radar with similar specifications will（）.

A.give better range performance in rain，hail，etc
B.display small targets in a mass of dense sea clutter at a greater range
C.have less sea return in choppy rough seas
D.display a more map like presentation for inshore navigation

单项选择题The 10-cm radar as compared to a 3-cm radar of similar specifications will（）.

A.be more suitable for river and harbor navigation
B.provide better range performance on low lying targets during good weather and calm seas
C.have a wider horizontal beam width
D.have more sea return during rough sea conditions

单项选择题SWEEP INT on radar panel is the abbreviation of（）.

A.sweep introduction
B.sweep interest
C.sweep intention
D.sweep intensity

单项选择题Radar reflectors are required for（）.

A.all fishing vessels over 39 feet in length
B.sail-propelled fishing vessels
C.all fishing vessels of less than 200 GT
D.wooden hull fishing vessels with a poor radar echo