[tex]\textit{surface area of a cylinder}\\\\ SA=2\pi r(h+r)~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ h=4\\ r=5 \end{cases}\implies \begin{array}{llll} SA=2\pi (5)(4+5)\implies SA=10\pi (9) \\\\\\ SA=90\pi \implies SA\approx 282.743~km^2 \end{array}[/tex]