单项选择题
A.Green star rocket B.Red star rocket C.Orange smoke signal D.Horizontal motion of a flag
What is the lifesaving signal for You are seen -assista...
单项选择题What is the lifesaving signal for You are seen -assistance will be given as soon as possible?（）
A.3 white star signals B.Horizontal motion with a white flag C.Vertical motion of a white light D.Code letter K by blinker light
Under the forces of its own weight，the suspended length...
单项选择题Under the forces of its own weight，the suspended length of line will fall into a shape known as a（）.
A.polygon B.holding arc C.catenary curve D.parabolic curve
There has been a collision in sea area of Fork.（）.A.Sta...
单项选择题There has been a collision in sea area of Fork.（）.
A.Stand by to give assistance B.Stand by to alter course C.Stand by to stop engine D.Stand by to go astern
