Question

What are the surface area and volume of a spherical barrel cactus with a radius of 5 inches?

Answer 1

$\bf \textit{surface area of a sphere}\\\\ SA=4\pi r^2~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r = 5 \end{cases}\implies SA=4\pi (5)^2 \\\\\\ SA=100\pi\implies SA\approx 314.16 \\\\[-0.35em] ~\dotfill\\\\ \textit{volume of a sphere}\\\\ V=\cfrac{4\pi r^3}{3}\qquad \qquad V=\cfrac{4\pi (5)^3}{3}\implies V=\cfrac{500\pi }{3}\implies V\approx 523.60$