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% define how the sections are rendered
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\begin{document}
\author{Benjamin Kuffel, Jim Martens\\Gruppe 6}
\title{Hausaufgaben zum 26. Januar}
\maketitle

\setcounter{section}{3}
\section{} % 13.4
    \subsection{}
    Die Prozessgraphen für \(t_6\) und \(t_7\) befinden sich auf \fref{fig:t6-graph} bzw. \fref{fig:t7-graph}.
    \begin{figure}
        \begin{tikzpicture}[node distance=1cm]
            \node (t6-start) {\((a + b) \leftmerge (b \cdot c)\)};
            \node (bc) [below=of t6-start] {\(b \cdot c\)};
            \node (c) [below=of bc] {\(c\)};
            \node (finish) [below=of c] {\(\surd\)};

            \path[->] (t6-start) edge[bend right] node[left] {\(a\)} (bc)
                (t6-start) edge[bend left] node[right] {\(b\)} (bc)
                (bc) edge node[right] {\(b\)} (c)
                (c) edge node[right] {\(c\)} (finish);
        \end{tikzpicture}
        \caption{Prozessgraph von \(t_6\)}
        \label{fig:t6-graph}
    \end{figure}

    \begin{figure}
        \begin{tikzpicture}[node distance=1cm]
            \node (start) {\(\partial_H((a \leftmerge (b + b) + (d \parallel e) \cdot b) \cdot c)\)};
            \node (a-left) [below left=of start] {\(\partial_H((b + b) \cdot c)\)};
            \node (de-right) [below right=of start] {\(\partial_H(b \cdot c)\)};
            \node (c) [below=3 of start] {\(\partial_H(c)\)};
            \node (finish) [below=of c] {\(\surd\)};

            \path[->] (start) edge node[above left] {\(a\)} (a-left)
                (start) edge node[above right] {\(f\)} (de-right)
                (a-left) edge[bend right] node[below left] {\(b\)} (c)
                (a-left) edge[bend left] node[above right] {\(b\)} (c)
                (de-right) edge node[above left] {\(b\)} (c)
                (c) edge node[right] {\(c\)} (finish);
        \end{tikzpicture}
        \caption{Prozessgraph von \(t_7\)}
        \label{fig:t7-graph}
    \end{figure}

\setcounter{section}{5}
\section{} % 13.6

\end{document}