Assume a certain adult requires \( 262 . \mathrm{mL} \) of pure oxygen per minute and assume inhaled air contains 20.0 percent oxygen by volume and exhaled air is 16.0 percent. (Also, assume that the volume of inhaled air is equal to that of the exhaled air.) If the person breathes 12.0 times every minute, what is the volume of air per breath? Round your answer to 2 significant digits.

To find the volume of air per breath, we first need to calculate the total volume of air the person inhales in one minute. Since the adult requires \( 262 \, \mathrm{mL} \) of pure oxygen per minute and the inhaled air consists of \( 20.0\% \) oxygen, we use the formula: \[ \text{Volume of air per minute} = \frac{\text{Volume of oxygen per minute}}{\text{Percentage of oxygen in inhaled air}} = \frac{262 \, \mathrm{mL}}{0.20} = 1310 \, \mathrm{mL} \] Next, we need to find the volume of air per breath. Since the person breathes \( 12.0 \) times per minute, we divide the total volume of air by the number of breaths: \[ \text{Volume of air per breath} = \frac{1310 \, \mathrm{mL}}{12.0} \approx 109.17 \, \mathrm{mL} \] Rounding this to two significant digits, we have: \[ \text{Volume of air per breath} \approx 110 \, \mathrm{mL} \] Thus, the volume of air per breath is approximately \( 110 \, \mathrm{mL} \).