From FDRâs brushes with death to Eleanorâs midnight ride with Amelia Earhart, here are 10 things you may not know about this presidential pair. 1. Franklin Roosevelt was related to 11 other presidents.
By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.y volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.
The answer is around twenty percent. Itâs true: even though we sometimes assume that all air is oxygen, only about a fifth of the atoms that make up our atmosphere are oxygen. The rest is things like nitrogen, carbon dioxide and hydrogen. Nevertheless, thatâs enough oxygen to breathe comfortably, so you can relax.