\begin{exercice}
 Voici la représentation en perspective cavalière d'un abri de jardin. 
 \begin{center}
  \begin{tikzpicture}[general, yscale=0.798, xscale=1.2]
  \draw[fill=J4] (0,2)--(0,0)--(2,0)--(3,1)--(3,3)--cycle;
  \draw[fill=B2] (0,2)--(2,2)--(3,3)--(2,5)--(1,4)--cycle;
  \draw (1,4)--(2,2)--(2,0);
  \draw[cote, color=A1] (0,-0.2)--(2,-0.2);
  \draw[cote, color=A1] (2,-0.2)--(3.2,1);
  \draw[cote, color=A1] (3.2,1)--(3.2,3);
  \draw[cote, color=A1] (3.2,3)--(3.2,5);
  \draw[color=A1] (1,-0.2) node[below] {\um{4}};
  \draw[color=A1] (2.6,0.6) node[below right] {\um{3}};
  \draw[color=A1] (3.2,2) node[right] {\um{2,8}};
  \draw[color=A1] (3.2,4) node[right] {\um{2,8}};
 \end{tikzpicture}
 \end{center}
\begin{enumerate}
 \item Construire le patron d'une maquette de cet abri \\au 1/100. 
 \item Calculer son volume.
\end{enumerate}
\begin{corrige}
\begin{enumerate}
 \item ~\\
 \begin{tikzpicture}[general, scale=0.25]
   \foreach \a/\b/\c/\d in {0/0/4/2.8, 0/2.8/4/5.8, 0/5.8/4/8.6, -2.8/2.8/0/5.8, 4/2.8/6.8/5.8} {\draw[fill=J4] (\a,\b) rectangle (\c,\d);}
   \foreach \a/\b/\c/\d in {6.8/2.8/10.24/5.8, -6.24/5.8/-2.8/2.8} {\draw[fill=B2] (\a,\b) rectangle (\c,\d);}
   \draw[fill=B2] (0,0)--(4,0)--(2,-2.8)--cycle;
   \draw[fill=B2] (0,8.6)--(4,8.6)--(2,11.4)--cycle;
  \end{tikzpicture}
  \item \umc{50,4}
\end{enumerate}
\end{corrige}
\end{exercice}
