Q2. Consider the mixed integer programming model below. Max Z = 2x1 + x2 S.t. x1 + x2 0 X1 integer Use branch and bound method to solve the problem as described in part a, b, c, d below. (60 P) a. State your Subproblem 1 and solve it graphically. b. State your Subproblem 2 and solve it graphically. c. State your Subproblem 3 and solve it graphically. d. Did you find an optimal solution at your current stage (yeso)? If yes, state your optimal solution, x*= ( x1, x2 ) and Z*. If no, state the interval for Z (lower and upper bound for Z) based on your calculations. Q2. Consider the mixed integer programming model below. Max Z = 2x1 + x2 S.t. x1 + x2 0 X1 integer Use branch and bound method to solve the problem as described in part a, b, c, d below. (60 P) a. State your Subproblem 1 and solve it graphically. b. State your Subproblem 2 and solve it graphically. c. State your Subproblem 3 and solve it graphically. d. Did you find an optimal solution at your current stage (yeso)? If yes, state your optimal solution, x*= ( x1, x2 ) and Z*. If no, state the interval for Z (lower and upper bound for Z) based on your calculations