[tex]\bf \textit{volume of a sphere}\\\\
V=\cfrac{4\pi r^3}{3}\qquad
\begin{cases}
r=radius\\
-----\\
V=72\pi
\end{cases}\implies 72\pi =\cfrac{4\pi r^3}{3}
\\\\\\
216\pi =4\pi r^3\implies \cfrac{216\pi }{4\pi }=r^3\implies \sqrt[3]{54}=r\implies \boxed{3\sqrt[3]{2}=r}\\\\
-------------------------------\\\\
\textit{surface area of a sphere}\\\\
S=4\pi r^2\implies S=4\pi \left( 3\sqrt[3]{2} \right)^2\implies S=4\pi 3^2\sqrt[3]{2^2}\implies S=4\pi 9\sqrt[3]{4}
\\\\\\
S=36\pi \sqrt[3]{4}[/tex]
