单项选择题 （）gives a description of the combined Cardinal and Lateral Buoyage system including textual and diagrammatic explanations of the five types of marks;lateral;cardinal,isolated danger;safe water and special marks.

单项选择题 A rigid replica of the International Code flag “A” may be shown by a vessel （）.

单项选择题 A report of casualty to a mobile offshore drilling unit must include （）.