Answer:
4. (answered below); 5. 66.2; 6. (answered below)
Explanation:
4. The individual's heart rate increased because the individual needs more oxygen supplied to their muscles so the heart has to pump the oxygenated blood through the body at a faster rate.
5. Take average of the number of the pulse before exercise:
(68 + 70 + 54 + 64 + 75) / 5 = 66.2
6. Different individuals are different sizes and are in different states of health. An individual who is more physically fit will have a slower rate rate because their heart muscle is "exercised" or worked more and pumps blood more efficiently.