Answer :
if the diameter is 16 inches, then its radius is half that, r = 8.
[tex]\bf \textit{surface area of a sphere}\\\\ A=4\pi r^2\quad \begin{cases} r=radius\\ -----\\ r=8 \end{cases}\implies A=4\pi 8^2[/tex]
[tex]\bf \textit{surface area of a sphere}\\\\ A=4\pi r^2\quad \begin{cases} r=radius\\ -----\\ r=8 \end{cases}\implies A=4\pi 8^2[/tex]