单项选择题
The directive force of a gyrocompass（）.
A.increases with latitude，being maximum at the geographic poles B.decreases with latitude，being maximum at the geographic equator C.is greatest when a vessel is near the Earth's magnetic equator D.remains the same at all latitudes
单项选择题 The difference between magnetic heading and compass heading is called（）.
单项选择题 The compass heading of a vessel differs from the true heading by（）.
单项选择题 The compass error of a magnetic compass that has no deviation is（）.
