TeX Quellcode:

\begin{array}{rcl} A_O & = & 2 \pi r(r+h) \cr A_O & = & 2 \pi \cdot 7{,}5 \, m\cdot(7{,}5 \, m+10 \, m) \cr A_O &\approx& 824{,}67 \,m^2 \end{array}