单项选择题
A fire starts on your vessel while refueling. You should FIRST（）.
A.stop the ventilation B.sound the general alarm C.determine the source of the fire D.attempt to extinguish the fire
单项选择题 A combination or all-purpose nozzle produces（）.
单项选择题 A CO2 portable extinguisher is annually checked by（）.
单项选择题 A CO2 extinguisher on a ship which has lost 10% of its charge must be（）.
