During a study, the temperature, in   degrees   Celsius   ° C , of the

The correct answer is $5$. For the graph shown, $x$ represents time, in minutes, and $y$ represents temperature, in degrees Celsius $\left(°\text{C}\right)$. Therefore, the average rate of change, in $°\text{C}$ per minute, of the recorded temperature of the air in the chamber between two x-values is the difference in the corresponding y-values divided by the difference in the x-values. The graph shows that at $x=5$, the corresponding y-value is $14$. The graph also shows that at $x=7$, the corresponding y-value is $24$. It follows that the average rate of change, in $°\text{C}$ per minute, from $x=5$ to $x=7$ is $\frac{24-14}{7-5}$, which is equivalent to $\frac{10}{2}$, or $5$.