Q. A 55-year-old man presents to his family care physician for a routine checkup. He denies any current issues and states he feels fine. Because he has a history of asthma and chronic bronchitis, a respiratory test and blood gas is performed. The man has a tidal volume of 0.45 L with a breathing frequency of 16 breaths/min. His arterial PCO2 is 41 mm Hg, and the PCO2 of his expired air is 35 mm Hg. What is his alveolar ventilation?