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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?

Deer cave cannot support photosynthesis is as not enough sunlight is present. in spite of this, it still has a complex food chain. what is the energy foundation of this food chain?

Acceleration is a direct result of a.) balanced forces b.) unbalanced forces c.) gravity d.) velocity