2010-II-19

$\begin{array}{cl}
= & 8\times 5 + 3 \times 7 \\
= & 61 \text{ cm}^2
\end{array}$

其底周界

$\begin{array}{cl}
= & 2(8+12) \\
= & 40 \text{ cm}
\end{array}$

所以，側面面積

$\begin{array}{cl}
= & 40 \times 14 \\
= & 560 \text{ cm}^2
\end{array}$

由此，該立體的總表面面積

$\begin{array}{cl}
= & 2\times 61 + 560 \\
= & 682 \text{ cm}^2
\end{array}$