Use Lingo to solve the crashing problem. Report the optimal solution found, as well as the optimal crashing cost. The following is the information relating to the problem.

The following table provides basic information about a construction project. Activity Activity Description Estimated Duration Immediate Predecessors A B D E A B C 2 weeks 4 weeks 10 weeks 6 weeks 4 weeks F E 5 weeks G D 7 weeks Excavate Lay the foundation Put up the rough wall Put up the roof Install the exterior plumbing Install the interior plumbing Put up the exterior siding Do the exterior painting Do the electrical work Put up the wallboard Install the flooring Do the interior painting Install the exterior fixtures Install the interior fixtures H I J K L M E, G F, I J J H 9 weeks 7 weeks 8 weeks 4 weeks 5 weeks 2 weeks N KL 6 weeks Time Cost Activity Normal Crash Normal Crash A B D E F G H J K L M N 2 weeks 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 1 week 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 $180,000 320,000 620,000 260,000 410,000 180,000 900,000 200,000 210,000 430,000 160,000 250,000 100,000 330,000 $280,000 420,000 860,000 340,000 570,000 260,000 1,020,000 380,000 270.000 490,000 200,000 350.000 200,000 510,000