单项选择题 On an OSV，when may a work vest be substituted for a required life jacket?（）

单项选择题 OAP IF ANY TO BE CHTRS ACCT BUT OWNERS CONTRIBUTION USD 0.3/MT. What does OAP stand for?（）

单项选择题 No jettison of cargo shall be made fair as（）unless such cargo is carried in accordance with the recognized custom of the trade.