Clark Construction is building a set of new condos in the Virginia Beach. The project consists of 18 buildings, each housing 12 condominiums. Each building will border the Virginia Beach Golf Course designed by J. M. Architects. The minimum price for a condominium unit is $300,000, and buyers expect a high-quality project. Response to the initial promotion was so great that CLARK Construction pre-sold all 216 units based solely on an architect's conception and schematic plans of the project. One reason for the quick sell-out may have been the -YOU CAN MOVE IN BY OCTOBER- campaign. As part of this campaign, CLARK promised rebates of $20,000 cash to all 216 buyers if all the facilities, buildings, and other amenities were not completed by October 15.

The following PERT/CPM network (image attached) details the precedence for the activities of the tasks remaining to be completed in the project. R and T will be subcontracted. Three-time estimates (in days) for each of the other activities needed for each condo have been determined and are given in the following table (Note: all the condos will be constructed concurrently) Use a full day as the smallest unit for scheduling the activities:

ACTIVITY CODE AND DESCRIPTION Estimated Activity Duration (a, m, b) Dependencies optimistic most likely pessimistic Al. Land measurements 5 8 11 B2. Layout of measurement stakes 7 12 17 A C3. Analysis of surrounding environment 10 17 24 D4. Building of foundation 12 22 32 B E5. Approval of construction papers 6 13 20 C F6. Layout of building framework 11 15 19 C G7. Gas line instalment 9 18 27 C H8. Electrical wiring 25 27 29 B, G 19. Interior plumbing 18 20 22 E, B J10. Wall construction 12 25 38 D, H K11. Insulation 10 23 36 I, F L12. Drywall 15 20 25 F, I M13. Roofing 3 10 17 K, J N14. Restaurant construction 25 40 55 G 015. Swimming pool 9 20 31 J, K, L, G P16. Fencing 6 10 14 J, K, L, G Q17. Telephone lines 12 22 32 M, O R18. Completion of underground M, O $19. Snack bar 10 20 30 N T20. Stream building N U.21 Outside lighting 8 12 16 P, S V22. Parking lots 3 5 7 P, S, Q, W23. Drainage construction 5 10 15 P, S, Q, T X24. Safety inspection 9 15 21 U, W Y25. Landscaping 6 24 42 R, V Z26. Final permits/releases 10 15 20 X, Y