下列哪些船舶应将航速减到能维持航向的最小速度?() ①与正横前的来船不能避免碰撞危险时; ②听到正横前来船的雾号,但尚未确定是否存在碰撞危险时; ③与正横前的来船不能避免紧迫局面时; ④当与正横前的来船不能避免紧迫危险时。
A. ①②③④
B. ②③④
C. ③④
D. ②③
The ratio of the height of a vessel’s rudder to its width is referred to as the().
A. aspect ratio
B. constriction ratio
C. rudder ratio
D. steering ratio