Answer: There is increase of 4.255 in the amount of carbon in the atmosphere.
Explanation:
Since we have given that
Concentration of carbon in Earth's atmosphere in 1800 = 280 ppm
Concentration of carbon in Earth's atmosphere in 2015 = 399 ppm
We need to find the percentage increase in the amount of carbon in the atmosphere.
So, Difference = 399-280 = 119 ppm
so, percentage increase in the amount of carbon is given by

Hence, there is increase of 4.255 in the amount of carbon in the atmosphere.