单项选择题
A.Dry chemicals B.CO2 C.Foam D.All the above
Which extinguishing agent is best for use on a magnesiu...
单项选择题Which extinguishing agent is best for use on a magnesium fire?（）
A.Water B.Sand C.CO2 D.Dry chemical
Which characteristic of Halon is a disadvantage when it...
单项选择题Which characteristic of Halon is a disadvantage when it is used as a fire extinguishing medium?（）
A.Leaves a residue B.Cost，relative to other agents C.Breaks down while under prolonged storage D.Conducts electricity
Which characteristic is an advantage of Halon as a fire...
单项选择题Which characteristic is an advantage of Halon as a fire extinguishing medium?（）
A.Electrically non-conductive B.Relatively inexpensive C.Effective against chemicals containing an oxidizer D.All of the above
