单项选择题
Which space（s）is（are）deducted from gross tonnage to derive net tonnage（）.
A.Boatswain's stores B.Companions and booby hatches C.Passenger spaces D.All of the above
单项选择题 Which space cannot be deducted from gross tonnage when calculating net tonnage（）.
单项选择题 Which of the following tensioning devices is used with webbing to secure light vehicles aboard Ro-Ro vessels（）.
单项选择题 Which of the following is a characteristic of a Ro-Ro vessel（）.
