20. A dangerous wreck in the position of 52°12’ North and 112°36’ East is marked by a ______ toindic
問題詳情
20. A dangerous wreck in the position of 52°12’ North and 112°36’ East is marked by a ______ toindicate the direction of safety water. (A) cardinal buoy (B) light boat (C) superbuoy (D) derelict vessel