In the optimal solution to the machine-to-job assignment problem, jobs 1 and 2 are both assigned to machine 4. Suppose we impose the restriction that jobs 1 and 2 must be assigned to different...

In the optimal solution to the machine-to-job assignment problem, jobs 1 and 2 are both assigned to machine 4. Suppose we impose the restriction that jobs 1 and 2 must be assigned to different machines. Change the model to accommodate this restriction and find the new optimal solution.

In the optimal solution to the machine-to-job assignment problem, jobs 3 and 4 are assigned to different machines. Suppose we impose the restriction that these jobs must be assigned to the same machine. Change the model to accommodate this restriction and find the new optimal solution.