4 A community project consists of 10 activities \(A , B , \ldots , J\), as shown in the activity network below.
\includegraphics[max width=\textwidth, alt={}, center]{372edcfa-c3cd-4c83-89e9-2bb5fd9825f1-06_899_1083_367_466} The duration of each activity is shown in days. 4

1. 1. Complete the activity network in the diagram above, showing the earliest start time and latest finish time for each activity. 4
2. (ii) State the minimum completion time for the community project.
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3. Write down the critical activities of the network.
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4. Glyn claims that a project's activity network can be used to determine its minimum completion time by adding together the durations of all the project's critical activities. 4
5. 1. Show that Glyn's claim is false for this community project's activity network.
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6. (ii) Describe a situation in which Glyn's claim would be true.