单项选择题
A vessel engaged in fishing during the day would show（）.
A.one black ball B.two cones with bases together C.a cone，apex downward D.two cones，apexes together
单项选择题 A vessel enagaged in fishing，and at anchor，shall show（）.
单项选择题 A vessel crossing a river on the Western Rivers has the right of way over（）.
单项选择题 A vessel continually lists to one side and has a normal rolling period. Which statement is TRUE?（）.
