Final answer:
The amount of air that a person can forcibly exhale after taking the deepest breath possible is known as the vital capacity (VC).
Step-by-step explanation:
If a person inhales as deeply as possible and then blows the air out until she cannot exhale any more, the amount of air that she expelled is her vital capacity (VC). The vital capacity is the maximum amount of air that can be forcibly exhaled after taking the deepest breath possible. This includes the tidal volume (TV), which is the amount of air inhaled during a normal breath; the inspiratory reserve volume (IRV), which is the amount of additional air that can be inspired after a normal inhalation; and the expiratory reserve volume (ERV), which is the amount of air that can be exhaled after a normal exhalation.
After forcefully exhaling, there is still a volume of air left in the lungs, known as the residual volume (RV), which is the air left in the lungs after a forced exhalation. Therefore, the total lung capacity (TLC) is the sum of all lung volumes, including the residual volume. The vital capacity is an essential measurement in pulmonary function testing and can vary based on factors like age, sex, height, and health of the individual