maldonadoashley89 maldonadoashley89 09-06-2021 Chemistry contestada Almost 99% of Earth's atmosphere is made up of two gases. What are the two gases and the percents of each? A) 21% oxygen and 78% nitrogen B) 21% water vapor and 78% oxygen 09 21% nitrogen and 78% oxygen D) 21% carbon dioxide and 78% oxygen