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No, it is higher or the CO2 would not move out of the lungs.
The lungs, the eyes, the ears.
With their lungs rather than through their lungs, but yes - both dolphins and kangaroos breathe with lungs.
Two vectors are identical when all their components are identical.
An alternative definition, for vectors used in physics, is that they are identical when both the magnitude and the direction are identical.
No. Humans have lungs but worms do not.