A. 0.3m B. 0.5m C. 0.6m D. 0.8m
A. 3等级 B. 4等级 C. 5等级 D. 6等级
A. Move bodily to port B. Move bodily to starboard C. Move in a zig-zag motion D. Steer a fairly straight course
A. 正确 B. 错误