Consider the following linear programming problem: Maximize 40 X1 + 30 X2 + 60X3 Subject to: X1 + X2 + X3 90 12 X1 + 8 X2 + 10 X3 1500 X1 , X2 , X3 0. How many slack, surplus, and artificial variables would be necessary if the simplex were used to solve this problem? Select one: a. 1 slack, 2 surplus, and 2 artificial b. 1 slack, 4 surplus, and 4 artificial c. 3 slack, 3 surplus, and 3 artificial d. 1 slack, 1 surplus, and 1 artificial