How to calculate carbon dioxide in 100kg of air?

The percentage of CO2 in  air is 0.04%.
therefore, mass of co2 in 100kg of air:
0.04/100 X 100 = 0.04 kg of CO2 itself. 

Ithink that the use of creativity in the sciences entails that one produce something out of nothing or from another thing. with this, i think that the he wrote down his results as four parts of the atomic theory is the manifestation of the  creativity of john dalton.