Answer
C = 66 in
A = 346$\frac{1}{2} in^{2}$
Work Step by Step
Given the radius of the circle = 10$\frac{1}{2}$in = $\frac{21}{2}$ in
The circumference of the circle is given by the formula
c= $\pi$ d = 2$\pi$ r
=2 * $\frac{22}{7}$ * $\frac{21}{2}$ = 66 in
The area A of a circle whose radius has length r is given by
A = $\pi r^{2}$cm
= $ \frac{22}{7} (\frac{21}{2})^{2}$
=$ \frac{22}{7} * \frac{21}{2} * \frac{21}{2} in^{2}$
=$\frac{33 * 21}{2} in^{2}$
= 346$\frac{1}{2} in^{2}$