单项选择题
A.limitations of radar equipment
B.presence of background lights at night
C.maximum horsepower of your vessel
D.maneuverability of your vessel
单项选择题 In determining if risk of collision exists the following considerations shall be among（）.
单项选择题 In a crossing situation on open waters，a sailing vessel shall keep out of the way of all the following vessels EXCEPT a vessel（）.
单项选择题 If your vessel is underway in fog and you hear one prolonged and three short blasts，this is a （）.