1 [Figures 1 and 2, printed on the insert, are provided for use in this question.]
A group of workers is involved in a building project. The table shows the activities involved. Each worker can perform any of the given activities.
| Activity | Immediate predecessors | Duration (days) | Number of workers required |
| A | - | 3 | 5 |
| B | A | 8 | 2 |
| C | A | 7 | 3 |
| \(D\) | \(B , C\) | 8 | 4 |
| E | C | 10 | 2 |
| \(F\) | C | 3 | 3 |
| \(G\) | D, E | 3 | 4 |
| H | \(F\) | 6 | 1 |
| I | \(G , H\) | 2 | 3 |
- Complete the activity network for the project on Figure 1.
- Find the earliest start time and the latest finish time for each activity, inserting their values on Figure 1.
- Find the critical path and state the minimum time for completion.
- The number of workers required for each activity is given in the table above. Given that each activity starts as early as possible and assuming there is no limit to the number of workers available, draw a resource histogram for the project on Figure 2, indicating clearly which activities take place at any given time.
- It is later discovered that there are only 7 workers available at any time. Use resource levelling to explain why the project will overrun and indicate which activities need to be delayed so that the project can be completed with the minimum extra time. State the minimum extra time required.