Using the network diagram and the additional information , find

1. The crash cost per day

2. Which activities should be crashed to meet a project deadline of 13 days at minimum cost. Assume partial crashing is allowed.

\begin{tabular}{|l|c|c|c|c|} \hline Activity & Crash Time (days) & Crashed Cost (total) & Normal Time (days) & Normal Cost \\ \hline A & 3 & $500 & 4 & $300 \\ \hline B & 1 & 325 & 3 & 250 \\ \hline C & 4 & 550 & 7 & 400 \\ \hline D & 3 & 250 & 5 & 150 \\ \hline \end{tabular}