单项选择题
If you have a liquefied flammable gas barge in tow，which is NOT required of you with respect to the barge and its cargo? （）
A.Make periodic inspections of bilges B.Keep the barge under constant surveillance C.Have a properly certificated tankerman or at least one licensed officer on board the towing vessel D.Verify ullage readings
单项选择题 Gasoline vapor tends to collect（）.
单项选择题 Gasoline tanks should be filled（）.
单项选择题 Gasoline fumes tend to（）.
