单项选择题
A.she can be observed by radar
B.she can be observed visually from the other vessel
C.she can be plotted on radar well enough to determine her heading
D.her fog signal can be heard
单项选择题 A vessel is approaching from dead ahead． Both of her sidelights are visible and her range lights are in line. Which of the following could you do first?（）.
单项选择题 A vessel has sustained damage in a collision with another vessel. It is necessary to have a Seaworthy Certificate before the vessel sails. Who will issue this certificate?（）
单项选择题 A vessel engaged in fishing underway sounds the same fog signal as a（）.