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given the following tasks for a small project, perform a CPM analysis to determine:

a) project duration

b) slack for each task

c) the set of tasks on the critical path

\begin{tabular}{|l|l|l|} \hline Task & Predecessors & Duration \\ \hline A & & 3 \\ \hline B & A & 2 \\ \hline C & A,B & 5 \\ \hline D & C, B & 6 \\ \hline E & C & 3 \\ \hline F & D,E & 7 \\ \hline \end{tabular}