4 A project is represented by the activity network below. The times are in days.
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- Explain the reason for each dummy activity.
- Calculate the early and late event times.
- Identify the critical activities.
- Calculate the independent float and interfering float on activity A .
- (a) Draw a cascade chart to represent the project, using the grid in the Printed Answer Booklet.
(b) Describe the effect on
- the project completion
- the critical activities
if the duration of activity D is increased by 5 days.
The number of workers needed for each activity is shown below.
| Activity | A | B | C | D | E | F | G | H |
| Workers | 2 | 1 | 1 | 2 | 1 | 1 | 1 | 1 |
The duration of activity D is 9 days. - Find the minimum number of workers needed.
You should explain your reasoning carefully.