单项选择题
A.hold a valid officer's license for inspected vessels
B.be a certificated tankerman
C.be 30 years old
D.have a letter from the company stating his qualification
单项选择题 To determine which grades of cargo a tanker is permitted to carry you should（）.
单项选择题 The type of carrier required to file a copy of freight tariffs would be the（）.
单项选择题 The safe working load for the assembled cargo gear and the minimum angle to the horizontal for which the gear is designed shall be marked on the（）.