Tripping defects in anchors frequently occur in（）.

What is the normal length of anchor cable used to anchor a vessel?（）

The transmission of messages respecting the dangers specified is free（）cost to the ships concerned.

To prevent a wooden hull from leaking you caulk it（）.

The use of the danger signal（）.

What form of ice is of land origin?（）

Which is NOT a distress signal?（）

Fog forms when the air（）.

The term OIL as used in the Oil Pollution Regulations means（）.

The radiotelephone safety message urgently concerned with safety of a person would be prefixed by the word（）.