Concept:A petrol fire is best extinguished by removing oxygen from the burning fuel.
Explanation:Petrol is a light, flammable liquid that floats on water.
Pouring water on a petrol fire would allow the petrol to spread and make the fire worse.
Carbon(IV) oxide, written as
CO2, is a heavy gas that does not support combustion.
When it is released over the fire, it covers the burning petrol and cuts off the oxygen supply.
Without oxygen, the fire is extinguished quickly and safely.
So, among the choices, carbon(IV) oxide is the most suitable substance for putting out a petrol fire.
Answer:B. carbon(IV) oxide