单项选择题
A.varies depending upon the bearing used
B.is the angular difference between magnetic north and compass north
C.is published on the compass rose on most nautical charts
D.is the angular difference between geographic and magnetic meridians
单项选择题 Knowing the compass heading that is 90°to the side of a ship will enable the operator of a survival craft to initially steer（）.
单项选择题 Indications of the master gyrocompass are sent to remote repeaters by the（）.
单项选择题 If the magnetic heading is greater than the compass heading，the deviation is（）.