As compared to carbon dioxide，dry chemical has which advantage?（）.

A.conducts electricity
B.should be directed at the base of the fire
C.is most effective on burning gases which are flowing
D.extinguishes by cooling oil fires below ignition temperature

A.meet
B.face
C.be in font of
D.follow

A.meet the applicable standards
B.be marked as additional equipment
C.be stowed in a separate area
D.All of the above