#### Answer

a) $49\pi\ ft^2$
b) $153.86\ ft^2$
c) $3.14$

#### Work Step by Step

The formula for the area of a circle uses the radius of the circle. The radius(r) is half the diameter(d).
$r=\frac{1}{2}d=\frac{1}{2}(14)=7\ ft$
a) Use the formula for the area of a circle..
$A=\pi r^2=\pi (7^2)=\pi\times49=49\pi$
b) $\pi$ is approximated as 3.14. Substitute to find the approximate area.
$A=49\pi=49(3.14)=153.86$
c) 3.14 is the standard approximation to use for $\pi$.