$ \text{Gegeben:}\\\text{Breite} \qquad b \qquad [m] \\ \text{Länge} \qquad a \qquad [m] \\ \\ \text{Gesucht:} \\\text{Fläche} \qquad A \qquad [m^{2}] \\ \\ A = a\cdot b\\ \textbf{Gegeben:} \\ b=9m \qquad a=8m \qquad \\ \\ \textbf{Rechnung:} \\ A = a\cdot b \\ b=9m\\ a=8m\\ A = 8m\cdot 9m\\\\A=72m^{2} \\\\\\ \small \begin{array}{|l|} \hline b=\\ \hline 9 m \\ \hline 90 dm \\ \hline 900 cm \\ \hline 9\cdot 10^{3} mm \\ \hline 9\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline a=\\ \hline 8 m \\ \hline 80 dm \\ \hline 800 cm \\ \hline 8\cdot 10^{3} mm \\ \hline 8\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline A=\\ \hline 72 m^2 \\ \hline 7,2\cdot 10^{3} dm^2 \\ \hline 7,2\cdot 10^{5} cm^2 \\ \hline 7,2\cdot 10^{7} mm^2 \\ \hline \frac{18}{25} a \\ \hline 0,0072 ha \\ \hline \end{array}$