Transcription: The air that we breathe is a mixture of gases and that mixture is perfect for the purpose of supporting life. 78% of this mixture is nitrogen, another 1% is a combination of several gases and 21% of the air that we breathe is made up of oxygen. Our bodies use oxygen in the chemical reactions which provide us with energy, the energy that we use to get through the day. If there weren't enough oxygen in the air we would not be able to produce the energy that we need to sustain ourselves. However, too much oxygen would be dangerous as well. Calculations indicate that for every 1% increase in the a ...
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