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The oxidizing agent our bodies use to obtain energy from food is oxygen (from the air). if you breathe 15 times a minute (at rest), taking in and exhaling 0.5 l of air with each breath, what volume of air do you breathe each day? air is 21% oxygen by volume. what volume of oxygen do you breathe each day?

Why do oceanic plates tend to subduction when colliding with a continental plate

Methane gas created by a cows flatulence especially in a large herd is a greenhouse gas. true or false.