单项选择题
A.Electrical wiring
B.Iron pipe
C.Radio
D.All of the above
单项选择题 Which is the correct procedure for anchoring a small to medium size vessel in deep water ().
单项选择题 Which is a weekly publication advising mariners of important matters affecting navigational safety().
单项选择题 What is the significance of the broken magenta lines which roughly parallel the shore between Roanoke Point and Orient Point on Long Island().