In the atmosphere, CO2 is about?

Explanation

The proportion of carbon dioxide in the atmosphere is about 0.03%Carbon dioxide is an important long-lived trace gas in Earth's atmosphere currently constituting about 0.03% of the atmosphere.Carbon dioxide concentrations are rising mostly because of the fossil fuels that people are burning for energy.Fossil fuels like coal and oil contain carbon that plants pulled out of the atmosphere through photosynthesis over the span of many millions of years