Question

By how much has atmospheric carbon dioxide concentration increased ever since the Industrial Revolution?

(a) 20%

(b) 10%

(c) 40%

(d) 60%

I had been asked this question during an interview.

Enquiry is from Greenhouse Gases in portion Atmosphere & Greenhouse Gases of Environmental Engineering

Answer 1

Correct choice is (c) 40%

To elaborate: Due to excessive combustion of fossil fuels, the carbon dioxide concentration shot up from 280ppm during 1750 to nearly 400ppm recently.