单项选择题
Any extinguishing agent used on a Class “C” fire must have which important property? （）
A.Cooling ability B.Leaves no residue C.Penetrating power D.Nonconductivity
单项选择题 Antares is found in what constellation?（）
单项选择题 An undocumented vessel with 10 people aboard and operating 25 miles off the seacoast must carry a survival craft of the（）.
单项选择题 An overtaking situation at night would be one in which one vessel sees which light(s) of a vessel ahead?（）
