Final answer:
Tidal volume (TV) is the amount of air inspired and expired during normal breathing, and although the exact formula isn't provided in the options, the closest correct answer is TV = VT + ERV, where 'VT' is assumed to represent tidal volume.
Step-by-step explanation:
The formula for calculating tidal volume (TV) is not directly listed among the options, but it can be inferred based on given information. Tidal volume (TV) is the amount of air that is inspired and expired during normal breathing. Vital capacity (VC), which is the sum of tidal volume (TV), expiratory reserve volume (ERV), and inspiratory reserve volume (IRV), represents the air volumes that participate in gas exchange. Therefore, the correct calculation would involve adding expiratory reserve volume (ERV) and inspiratory reserve volume (IRV). However, given the choices, the closest correct formula would be: d) TV = VT + ERV, assuming 'VT' represents tidal volume.