if it has a base diameter of 10, that means its base radius is half that, or 5.
[tex]\textit{surface area of a cylinder}\\\\ SA=2\pi r(h+r)~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ h=7\\ r=5 \end{cases}\implies \begin{array}{llll} SA=2\pi (5)(7+5) \\\\\\ SA=10\pi (12)\implies SA=120\pi \\\\\\ \stackrel{using~\pi =3.14}{SA=376.8~yd^2} \end{array}[/tex]