单项选择题
Which nautical charts are intended for coastwise navigation outside of outlying reefs and shoals（）.
A.Approach charts B.General charts C.Sailing charts D.Coast charts
单项选择题 Which instrument is used to predict the approach of a low pressure system（）.
单项选择题 Which effect does speed through the water have on a vessel which is underway in shallow water （）.
单项选择题 When liquid is free to move transversely in a tank，the effect is called（）.
