What do you need help with
One way in determining your fitness level is trying to do a Full Sprint Run and holding your breath for as long as you can. That way you can determine your cardiovascular capacity and lung capacity. On improving your fitness levels you should do swimming, jogging and of course a balanced diet.
The correct answer is B. controlling the flow of blood to the skin
The more blood there is, the more heat there will be because of blood. An easy example is when someone's ears get all red due to a blood rush to the ears. At that time, ears are also very warm.
