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
A、网规对象树没有节点,GIS地图能显示小区 B、网规对象树没有节点,GIS地图不能显示小区 C、网规对象树有节点,GIS地图能显示小区 D、网规对象树有节点,GIS地图不能显示小区