there are fifteen pounds of CO2 in the container
the container，when full，weighs fifteen pounds
the pressure at the discharge nozzle is l5 psi
the empty container weighs fifteen pounds
第1题：
A portable dry chemical fire extinguisher discharges by ______.
A.gravity when the extinguisher is turned upside down
B.pressure from a small CO2 cartridge on the extinguisher
C.air pressure from the hand pump attached to the extinguisher
D.pressure from the reaction when water is mixed with the chemical
第2题：
How do you operate a portable CO2 fire extinguisher?______.
A.Point the horn down
B.Turn cylinder upside-down
C.Break the rupture disc
D.Pull pin, squeeze grip
第3题：
(A) so long as
(B) unless
(C) so that
(D) because
正确答案：B
解答参考：B.so long as：只要;unless：除非;so that：以便;because：因为。【译文】星期五董事们要开会，除非没有事要讨论。
第4题：
引起温室效应、酸雨、臭氧空洞的主要气体污染依次是（）
第5题：
Why is Australia.s New South Wales called the premier state?（）
第6题：
After using a CO2 portable extinguisher, it should be ______.
A.put back in service if some CO2 remains
B.hydrostatically tested
C.retagged
D.Recharged
第7题：
In order to discharge a CO2 portable fire extinguisher, the operator must FIRST ______.
A.invert the CO2 extinguisher
B.squeeze the two trigger handles together
C.remove the locking pin
D.open the discharge valve
第8题：
A、CO 2、SO2、O2
B、CO2、SO2、NO、O2
C、CO2、SO2、NO、H2O、O2
D、SO 2、NO2、N2、CO2
第9题：
Why is the southern area of the Northern Territory called the Red Centre of Australia?（）
第10题：
（）is best for electrical fire.