4.Use the table from Problem 31 on page 409 for a, b, and c below.

a.Neatly construct the network and identify the critical path.

b.Using the information in the table, compute the total allowable crash time and crash cost per week for each activity. (similar to the last 2 columns in table 8.4 on page 378)

c.If you can only crash one activity, which one do you crash and why?

31. The following table provides the information necessary to construct a project network and project crash data: Activity Time (weeks) Activity Cost Crash Normal Normal Crash Activity (ij) Activity Predecessor 20 a 24 8 20 7 b (1,2) (1,4) (1,3) (2,4) (3, 4) $1,000 1,200 700 500 550 $1,480 1,400 1,190 820 730 14 10 11 6 a d 5 e 378 CHAPTER 8 PROJECT MANAGEMENT The normal times and costs, the crash times and costs, the total allowable crash times, and the crash cost per week for each activity in the network in Figure 8.19 are summarized in Table 8.4. Recall that the critical path for the house-building network encompassed activities 1-2-47, and the project duration was 9 months, or 36 weeks. Suppose that the home builder needed the house in 30 weeks and wanted to know how much extra cost would be incurred to complete the house in this time. To analyze this situation, the contractor would crash the project network to 30 weeks, using the information in Table 8.4. Normal Time (weeks) Crash Time (weeks) Normal Cost Crash Cost Total Allowable Crash Time (weeks) Crash Cost per Week TABLE 8.4 Normal activity and crash data for Activity the network in 1 Figure 8.19 2 3 12 7 8 5 5 3 1 3 3 4 9 4 12 4 4 S 3,000 2.000 4.000 50,000 500 500 15.000 $75,000 $ 5,000 3,500 7,000 71,000 1,100 1,100 22.000 $110.700 $ 400 500 3,000 7.000 200 200 7,000 3 5 6 7 1 1 3 3 1 4