单项选择题
A.one year
B.two years
C.four years
D.five years
单项选择题 Prior to a ship’s departure, （） may not always be tested.
单项选择题 Prior to a ship’s departure from any port （） should be tested with deck officer to ensure satisfactory operation.
单项选择题 The（）is a series of trials done at sea to determine whether the ship has met the specifications of design, modification, or repair.