\ANG{
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\begin{minipage}[t]{9cm}
Man berechne Umfang und Inhalt der schattierten Fl"ache!
\end{minipage}
\hfill
\raisebox{-42mm}{\begin{minipage}[t]{7cm}
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\setplotarea x from 0 to 14, y from 0 to 10
\plot 1 2  13 2  7 8  1 2 /
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\plot 7 2  7 8 /
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\vshade 5.24 6.24 6.24 <1pt,z,3pt,1pt> 6 5.32 5.72  7 2 5.51
        <z,1pt,3pt,1pt> 8 5.32 5.72  8.76 6.24 6.24 /
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\put {\circle*{2}} [Bl] at 7.2  7.5
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}
\LSG{ $U=a\cdot \frac{\sqrt{2}}{2}\cdot \pi;~A=a^2\cdot (1-\pi+\frac{\pi}{2}\sqrt{2})$
}