Volume is one half of the information you need. Pressure is the other half.So volume means nothing regarding diving, how long of a dive can I do with a 13l tank at 0 psi?
Are you actually having a hard time grasping this or just being obtuse?
If you are legitimately having a hard time wrapping your head around it, feel free to call me and we can work through it over the phone. I can text you my number.
If you are just being a dousche, I am done here.