Answer:
Carbon dioxide
Explanation:
Because The heart pumps the oxygen to the muscles that are doing the exercise. When you exercise and your muscles work harder, your body uses more oxygen and produces more carbon dioxide.
I believe you are talking about introverts, but I dont completely understand your question...
Answer:
You need protein in your diet to help your body repair cells and make new ones. Protein is also important for growth and development in children, teens, and pregnant women.
Explanation:
Hope this helps :) Have an amazing day and enjoy your assignment!!