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25. (Multiple Choice) (10 pts.) The constraints of a two-variable linear programming problem are stated here: X21; Y2 1; X+Y5 9. Which of the following statements regarding the (X, Y) points is NOT TRUE? a) The optimal solution might be X=1, Y=8 b) The optimal solution might be X=4, Y=4 c) The optimal solution might be X=1, Y=1 d) The optimal solution might be X=8, Y=1 e) We need to know the objective function to make a better statement. f) All of the above are TRUE