Answer Happy

2. Fig. 2 (see overleaf) shows the AOA network of a construction project, with the precedence relationships and the activity durations indicated. The total costs of the different activities are summarized in the following table: Activity 1-2 2-3 2-4 2-5 3-6 4-6 4-7 5-7 6-8 7-8 8-9 Duration (weeks) 2 10 10 8 6 4 8 6 6 5 3 Total Cost ($) 4,800 16,000 18,000 16,800 15,000 8,000 17,600 15,600 16,200 10.500 6,900 The mark-up for the activities on the critical path is 15% and for the other activities is 10%. Progress measurements are made every four weeks with payments due four weeks later. 11% retention money is required for the project. The work on all the activities is to start at their earliest start times and to continue without delay. The value of work in progress is to be proportional to the time spent on it. (a) Draw: i) the S-curve; ii) the cumulative value vs. time curve; and iii) the cumulative income curve. (b) Draw the cash flow graph over the duration of the project. (c) Draw a graph of working capital vs. time. (d) What is the total profit expected from the project? 5 8 6 10 8 5 1 3 4 7 8 9 10 4 6 3 6 Figure 2: AOA Network Diagram