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\begin{frame}
  \frametitle{Exercises}
 
  \begin{minipage}{0.49\textwidth}
  \begin{center}
    \begin{tikzpicture}[
        default,
        point/.style={circle, draw=blue, thick, inner sep=3pt, minimum size=9mm},
        node distance=20mm]
  
      \node (1) [point] {\lab{p}};
      \node [alo=1] {$w_1$};
      
      \node (2) [point, below left of=1] {\lab{q}};
      \node [alo=2] {$w_2$};

      \node (3) [point, below right of =1] {\lab{p,\;r}};
      \node [aro=3] {$w_3$};

      \begin{scope}[shorten <= 1mm, shorten >= 1mm, very thick,>=stealth]
        \draw [->] (1) to[bend left=15] (2);
        \draw [->,red] (2) to[bend left=15] (1);
        \draw [->] (1) to (3);
        \draw [->] (3) to (2);
      \end{scope}

      \draw [rounded corners=2mm, dashed] (-25mm,-20mm) rectangle (25mm,8mm);
    \end{tikzpicture}
    \vspace{1ex}
  \end{center}
  \end{minipage}
  \begin{minipage}{0.50\textwidth}
    \begin{itemize}  
    \item  $\BLUE{W}= \{w_1,w_2,w_3\}$
    \item  $R = \{\langle w_1,w_2\rangle ,\langle w_1,w_3\rangle, $ \\
    \;\hfill $ \langle w_2,w_1\rangle , \langle w_3,w_2\rangle \}$
    \item  $\lab{L}(w_1) = \{\lab{p}\}$ \\
           $\lab{L}(w_2) =\{ \lab{q}\}$ \\
           $\lab{L}(w_3) =\{ \lab{p,r}\}$
    \end{itemize}    
  \end{minipage}
  \medskip
  
  \begin{exampleblock}{Check for yourself:}
    \begin{malign}
    w_2 &\;\models\; \all r \wedge \all p & \mbox{\DARKRED{?}}\\
    w_1 &\;\models\; \all p               & \mbox{\DARKRED{?}}\\ 
    w_1 &\;\models\; \some \all p         & \mbox{\DARKRED{?}}\\
    w_1 &\;\models\; \all  \some  p       & \mbox{\DARKRED{?}}
    \end{malign}
  \end{exampleblock}
\end{frame}