单项选择题
There are often three parts in a weather report, not including（）
A.warning B.general synopsis C.forecast D.traffic density
单项选择题 Which of the following is defined as static information of AIS?（）
单项选择题 When hitting a solid object such as ship or an airplane,the radar waves are reflected back（）they came.
单项选择题 What does SSO stand for regarding ship security?（）
