Question

Inspite of breathing out co2 in alarge amount & released by combustion the atmosphere has more fraction of co2 only why?

Answer 1

Not only human beings releases co2 into the atmosphere but also the animals releases co2 into the atmosphere..even plants do release some amount of co2...
By using lot of fuels in vehicles also releases co2 and due burning of wood and other things also releases co2 into the atmosphere..
HENCE CO2 IS PRESENT IN A LARGE AMOUNT...