When it involves granting favors it's called quid pro quo.
Swimming, any type of cardio that requires a lot of breathing
Alveoli small balloon-like structures which are responsible for the oxygen exchange in the lungs across the membranes. These are attached to the branches of the bronchial passages. These alveoli inflate and deflate with inhalation and exhalation. Answer is C.
B, weakens the immune system
The intestines do
hope I helped
