What is the approximate composition of the dry air by volume in the troposphere?
Domanda 121, Meteorology - ATPL - Airline Transport Pilot license
| 88 % oxygen, 9 % nitrogen, and the rest other gasses |
| 10 % oxygen, 89 % nitrogen, and the rest other gasses |
| 50 % oxygen, 40 % nitrogen, and the rest other gasses |
| 21 % oxygen, 78 % nitrogen, and the rest other gasses |
