#### Answer

(a)
$S(2)=16\pi \approx 50.27$
$S(3)=36\pi \approx 113.10$
(b) surface areas

#### Work Step by Step

(a) We are given:
$S(r)=4\pi r^2$
$S(2)=4\pi (2)^2=16\pi \approx 50.27$
$S(3)=4\pi (3)^2=36\pi \approx 113.10$
(b) The values in (a) represent the surface areas of a sphere of radius $2$ and $3$ units, respectively..