Which statement about the gyrocompass is FALSE（）.

单项选择题Which statement about the Flinders bar of the magnetic compass is CORRECT（）.

A.It compensates for the error caused by the vertical component of the Earth's magnetic field
B.It compensates for error caused by the heeling of a vessel
C.It compensates for quadrantal deviation
D.It is only needed in equatorial waters

单项选择题Which magnetic compass corrector（s）CANNOT be set on a heading of magnetic east or magnetic west（）.

A.Heeling magnet
B.Flinders bar
C.Fore-and-aft magnets
D.All of the above can be set on magnetic east or magnetic west headings

单项选择题Which magnetic compass corrector（s）can be set while the vessel is on a heading of magnetic north or magnetic south（）.

A.Quadrantal spheres
B.Heeling magnets
C.Flinders bar
D.Fore-and-aft magnets

单项选择题Which compensates for errors introduced when the vessel heels over（）.

A.The soft iron spheres on the arms of the binnacle
B.Magnets placed in trays inside the binnacle
C.A single vertical magnet beneath the compass
D.The Flinders bar

单项选择题When relieving the helm，the new helmsman should know the（）.

A.Course per magnetic steering compass
B.Gyro error
C.Variation
D.Maximum rudder angle previously used