Answer:
It should be subjective data.
Because the more someone exerts themselves the more oxygen and carbon dioxide out put ratio is greater. The more you run and the faster you run the more oxygen you loose which is supplied to your muscles including your lungs.
Answer:
B
Explanation:
Because of the fact that you are not the only one who has been in the same life as a friend.
Get regular check ups, ask a doctor about lung health and breathing
C. you need shoes with more cushioning and flexibility
