Answer Happy

We next apply the subtour constraint generation method to find a solution to this problem; we use binary variable ze to represent whether edge e is selected, for all edges e. The initial Integer 14 Programming model, without any subtour constraints, has been implemented and solved with Excel Solver. The solution is provided in the figure at the top of the next page. The cells representing the edges and associated variables, in columns B to E, have been sorted by largest variable value. Thus, the cells below E15 all have value 0. D Sum of 2 Edge: 1) Distance Select Location edges с G H K 1 2 1 NO EN 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 D D 1 2 2 3 4 5 8 D 2 3 4 9 4 6 8 3 7 5 6 7 9 1 8 4 7 5 4 2 4 S 5 3 4 4 5 6 12 9 1 1 1 1 1 1 1 1 1 이 0 0 0 NNNNNNNNN Total Length 40 1. (2pt) Does the Excel solution represent a single tour? If not, write down the subtours that it represents. 2. (4pts) For each of the subtours found under (d), write down the subtour elimination con- straint(s). 3. (2pt) If you were to add your subtour elimination constraints to the initial IP model and resolve, do you expect the objective value to increase or decrease? Explain.