$\begin{array}{l} \text{Gegeben:}\\\text{Winkel} \qquad \alpha \qquad [^{\circ}] \\ \text{Kreiszahl} \qquad \pi \qquad [] \\ \text{Radius} \qquad r \qquad [m] \\ \\ \text{Gesucht:} \\\text{Fläche} \qquad A \qquad [m^{2}] \\ \\ A = \frac{r^{2} \cdot \pi \cdot \alpha }{ 360}\\ \textbf{Gegeben:} \\ \alpha=40^{\circ} \qquad \pi=3\frac{16}{113} \qquad r=5m \qquad \\ \\ \textbf{Rechnung:} \\ A = \frac{r^{2} \cdot \pi \cdot \alpha }{ 360} \\ \alpha=40^{\circ}\\ \pi=3\frac{16}{113}\\ r=5m\\ A = \frac{(5m)^{2} \cdot 3\frac{16}{113} \cdot 40^{\circ} }{ 360}\\\\A=8,73m^{2} \\\\\\ \small \begin{array}{|l|} \hline alpha=\\ \hline 40 ° \\ \hline 2,4\cdot 10^{3} \text{'} \\ \hline 1,44\cdot 10^{5} \text{''} \\ \hline 44\frac{4}{9} gon \\ \hline 0,698 rad \\ \hline \end{array} \small \begin{array}{|l|} \hline r=\\ \hline 5 m \\ \hline 50 dm \\ \hline 500 cm \\ \hline 5\cdot 10^{3} mm \\ \hline 5\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline A=\\ \hline 8,73 m^2 \\ \hline 873 dm^2 \\ \hline 8,73\cdot 10^{4} cm^2 \\ \hline 8726646\frac{7}{18} mm^2 \\ \hline 0,0873 a \\ \hline 0,000873 ha \\ \hline \end{array} \end{array}$