You're moving the goalposts IQ boy. We are discussing wearing...

You're moving the goalposts IQ boy. We are discussing wearing masks and hypoxia not suffocation. So please explain how wearing a mask gives you hypoxia when the compound of breathe exhaled is nearly the same as that of which you breathe in?

Or are you about to tell me the human lungs have the ability to change the composition of air? (I know there is a slight decrease in O2 and a slight increase in CO2 on exhalation)