The datum from which the predicted heights of tides are reckoned in the tide tables is（）.

单项选择题The dangerous semicircle of a typhoon in the Southern Hemisphere is that area（）.

A.measured from due south clockwise 180°
B.measured from due south counterclockwise 180°
C.to the left of the storm's track
D.ahead of the typhoon measured from the storm's track to 90°on each side

单项选择题The dangerous semicircle of a hurricane in the Northern Hemisphere is that area of the storm （）.

A.to the right of the storm's track
B.measured from true north clockwise to 180°T
C.measured from true north counterclockwise to 180°T
D.between the ship's heading and the bearing to the eye

单项选择题The damage to a vessel is over $25，000. Who must notify the nearest Coast Guard Marine Safety or Marine Inspection Office as soon as possible? （）

A.The owner of the vessel
B.The Master of the vessel
C.The person in charge of the vessel at the time of casualty
D.Any one of the above

单项选择题The damage to a vessel is over $25，000. Who must notify the nearest Coast Guard Marine Safety or Marine Inspection Office as soon as possible? （）

A.The Master of the vessel
B.The Radio Officer
C.The Chief Officer
D.All of the above

单项选择题The damage to a vessel is over $25，000. Who must notify the nearest Coast Guard Marine Safety or Marine Inspection Office as soon as possible? （）

A.The owner of the vessel
B.The Master of the vessel
C.The person in charge of the vessel at the time of casualty
D.Any one of the above