a) Recall that to evaluate a function at a given value, we substitute the variable by the given value.
Therefore, evaluating C(h) at h=6 we get:
[tex]C(6)=76+24\cdot6.[/tex]Simplifying the above result we get:
[tex]\begin{gathered} C(6)=76+144 \\ =220. \end{gathered}[/tex]b) Setting C(h)=364 we get:
[tex]76+24h=364.[/tex]Subtracting 76 from the above equation we get:
[tex]\begin{gathered} 76+24h-76=364-76, \\ 24h=288. \end{gathered}[/tex]Dividing the above equation by 24 we get:
[tex]\begin{gathered} \frac{24h}{24}=\frac{288}{24}, \\ h=12. \end{gathered}[/tex]Answer:
(a) $220.
(b) 12.