单项选择题
A.Vector chart format
B.Raster chart data
C.pixel
D.Electronic Nautical Chart
单项选择题 The heading of a vessel is indicated by what part of the compass? （）
单项选择题 The correction to be applied to a Loran-C reading when matching a sky wave to a ground wave may be found（）.
单项选择题 The basic collision avoidance display presented by CASII is designed for easy interpretation and（）of possible collision threat situations.