$ \text{Gegeben:}\\\text{Kreiszahl} \qquad \pi \qquad [] \\ \text{Fläche} \qquad A \qquad [m^{2}] \\ \text{Radius} \qquad r \qquad [m] \\ \\ \text{Gesucht:} \\\text{Winkel} \qquad \alpha \qquad [^{\circ}] \\ \\ \alpha = \frac{A\cdot 360}{r^{2} \cdot \pi }\\ \textbf{Gegeben:} \\ \pi=3\frac{16}{113} \qquad A=9m^{2} \qquad r=3m \qquad \\ \\ \textbf{Rechnung:} \\ \alpha = \frac{A\cdot 360}{r^{2} \cdot \pi } \\ \pi=3\frac{16}{113}\\ A=9m^{2}\\ r=3m\\ \alpha = \frac{9m^{2}\cdot 360}{(3m)^{2} \cdot 3\frac{16}{113} }\\\\\alpha=115^{\circ} \\\\ \small \begin{array}{|l|} \hline A=\\ \hline 9 m^2 \\ \hline 900 dm^2 \\ \hline 9\cdot 10^{4} cm^2 \\ \hline 9\cdot 10^{6} mm^2 \\ \hline \frac{9}{100} a \\ \hline 0,0009 ha \\ \hline \end{array} \small \begin{array}{|l|} \hline r=\\ \hline 3 m \\ \hline 30 dm \\ \hline 300 cm \\ \hline 3\cdot 10^{3} mm \\ \hline 3\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline alpha=\\ \hline 115 ° \\ \hline 6,88\cdot 10^{3} \text{'} \\ \hline 4,13\cdot 10^{5} \text{''} \\ \hline 127 gon \\ \hline 2 rad \\ \hline \end{array}$