What is NOT a characteristic of carbon dioxide fire-extingui

A、emission

B、emit

C、radiation

D、evaporation

In the event of fire in a machinery space，______.

A.the fixed carbon dioxide system should be used only when all other means of extinguishment have failed

B.the fixed carbon dioxide system should be used immediately，as it is the most efficient means of extinguishment

C.water in any form should not be used as it will spread the fire

D.the space should be opened 5 minutes after flooding CO2 to prevent injury to personnel

A. rate

B. proportion

C. extent

D. amount

The most effective way of applying carbon dioxide from a portable extinguisher to a fire is by ______．

A.Forming a cloud cover over the flames

B.Directing the gas at the base of the flames in a slow sweeping motion

C.Discharging the carbon dioxide into the heart of the flames

D.Bouncing the discharge off an adjacent bulkhead just above the burning surface

Theoretical perfect combustion in a diesel engine yields by-products of_____.

A.aldehydes and carbon dioxide

B.water vapor and carbon monoxide

C.nitrogen and carbon monoxide

D.water vapor and carbon dioxide

What could result in an incorrect oxygen concentration reading on the oxygen indicator ________．

A.Exposure to carbon dioxide for no more than 1 minute

B.Exposure to carbon dioxide for more than 10 minutes

C.Exposure to a very low concentration of sulfur dioxide for no more than 2 minutes

D.None of the above

What does the word “this” underlined in the third paragraph refer to?

A．We will lose much more than we can gain．

B．Humans have begun destroying rainforests．

C．People have a strong desire for resources．

D．Much carbon dioxide comes from burning rainforests．

______, as the chemical extinguisher agent, should be used for an electric fire.

A.dry chemical or foam

B.foam or soda acid

C.carbon dioxide or foam

D.carbon dioxide or dry chemical