The following table provides basic information about a construction project. Activity Activity Description Immediate Estimated Duration Predecessors A Excavate 2 weeks B Lay the foundation A 4 weeks Put up the rough wall B 10 weeks D Put up the roof 6 weeks E Install the exterior 4 weeks plumbing F Install the interior E 5 weeks plumbing G Put up the exterior D 7 weeks siding H Do the exterior painting E, G 9 weeks I Do the electrical work 7 weeks J Put up the wallboard F, I 8 weeks K Install the flooring J 4 weeks L Do the interior painting J 5 weeks M Install the exterior H 2 weeks fixtures N Install the interior K, L 6 weeks fixtures (a) Draw the project network. (b) Under normal circumstances, can the project be completed within 40 weeks? Why? (c) What are the critical activities? (d) What is the critical path of the project? Consider the additional information below: Time Cost Activity Normal Crash Normal Crash A 2 weeks 1 week $180,000 $ 280,000 Consider the additional information below: Time Cost Activity Normal Crash Normal Crash A 2 weeks 1 week $180,000 $ 280,000 Time Cost Activity Normal Crash Normal Crash B D E F G H I J K L M N 4 weeks 10 weeks 6 weeks 4 weeks 5 weeks 7 weeks 9 weeks 7 weeks 8 weeks 4 weeks 5 weeks 2 weeks 6 weeks 2 weeks 7 weeks 4 weeks 3 weeks 3 weeks 4 weeks 6 weeks 5 weeks 6 weeks 3 weeks 3 weeks 1 week 3 weeks 320,000 620,000 260,000 410,000 180,000 900,000 200,000 210,000 430,000 160,000 250,000 100,000 330,000 420,000 860,000 340,000 570,000 260,000 1,020,000 380,000 270,000 490,000 200,000 350,000 200,000 510,000 (e) Formulate an LP model to determine an optimal crashing for each of the activities in order to complete the project within 40 weeks