Submitted by kslcom2514 in science
Oxygen accounts for about 21% of Earth's air, with the rest of our atmosphere primarily nitrogen. And most living things - including people, as we well know - need oxygen to survive.
Submitted by kslcom2514 in science
Oxygen accounts for about 21% of Earth's air, with the rest of our atmosphere primarily nitrogen. And most living things - including people, as we well know - need oxygen to survive.