The lungs recoil to force the air out of the lungs. The intercostal muscles relax, returning the chest wall to its original position. The diaphragm also relaxes, moving higher into the thoracic cavity.
Answer: because gas rise in upward
Explanation:
A. Measure your heart rate before, and after workouts
Answer:
The awnser is B you should use stress managment techniques
Explanation: