7. \begin{figure}[h] \end{figure} A company models a project by the activity network shown in Figure 5. The activities are represented by the arcs. The number in brackets on each arc gives the time, in days, to complete the activity. Each activity requires exactly one worker. The project is to be completed in the shortest possible time.

1. Add early and late event times to Diagram 1 in the answer book.
2. State the critical path and its length.
3. On Diagram 2 in the answer book, construct a cascade (Gantt) chart.
4. By using your cascade chart, state which activities must be happening at
   1. time 7.5
   2. time 16.5 It is decided that the company may use up to 25 days to complete the project.
5. On Diagram 3 in the answer book, construct a scheduling diagram to show how this project can be completed within 25 days using as few workers as possible.