if you swim a significant amount you’ll learn how much time is spent on it, and if you try breathing water you’ll start craving oxygen (well probably more craving the removal of co2), also I would imagine that oil refineries could be considered places where oxygen is dangerous but people still use.
if you swim a significant amount you’ll learn how much time is spent on it, and if you try breathing water you’ll start craving oxygen (well probably more craving the removal of co2), also I would imagine that oil refineries could be considered places where oxygen is dangerous but people still use.