What percentage of oxygen is contained in exhaled air? by Sunday | Apr 29 | Biology NECO | 0 comments A. 21% B. 16% C. 4% D. 0.04% E. Less than 0.01% Correct Answer: Option B – 16% Users Also Read These:Exchange of gases takes place in the air sacs…The system of election whereby each political party…In the laboratory preparation of oxygen; dried…What is the percentage by mass of oxygen in…What volume of oxygen will be left unreacted when a…