ANSWER
6 inches
EXPLANATION
The given function is
[tex]h(t) = - {t}^{2} + 12t + 10[/tex]
The average rate of change from t=1 to t=5 is given by:
[tex] = \frac{h(5) - h(1)}{5 - 1} [/tex]
[tex]h(5) = - {(5)}^{2} + 12(5) + 10[/tex]
[tex]h(5) = - 25 + 60+ 10[/tex]
[tex]h(5) = 45[/tex]
Also,
[tex]h(1) = - {(1)}^{2} + 12(1) + 10[/tex]
[tex]h(1) = - 1+ 12+ 10[/tex]
[tex]h(1) = 21[/tex]
The average rate of change is now
[tex] = \frac{45 - 21}{4} [/tex]
[tex] = \frac{24}{4} [/tex]
[tex] = 6[/tex]