Despite the rising importance and great convenience of the gyrocompass,the magnetic compass still retain its importance because of its（）.

A.A ship-to-ship mode
B.A ship-to-shore mode
C.Integrated with a vessel traffic system
D.Sending out information through broadcast automatically

A.The funnel
B.The messroom
C.The galley
D.The satellite antenna

A.synchronous rolling occurs
B.roll period decreases
C.roll period increases
D.roll amplitude is dampened