相关考题
-
单项选择题
CO2 and Halon extinguishers are used for electrical fire, as well as （）fire.
A.common
B.oil
C.electrical
D.chemical -
单项选择题
Lifeboat launching is operated at intervals of （）months.
A.one
B.two
C.three
D.four -
单项选择题
Fire drill is carried out once a （）.
A.year
B.day
C.week
D.month
