It’s really living environments but I didn’t have that option but please help me I can’t fail

Answer:
During exercise heart rate increases to accommodate for the increased need of oxygen through out body as well as to increase stroke volume (force and rate in which blood is expelled to the rest of the body). After exercising the rate in which your heart beats returns to a resting state (decreases) to reflect the decrease in the need for oxygen throughout your body.
Explanation: