many decision variables are required in the formulation of this problem? Let X31 be the number of X3 produced without discount, X32 be the number of X3 produced with discount. Which of the following pairs of constraints enforces the quantity discount relationship on X3? A. X31M3Y3,X3270Y3 B. X31M3Y3,X3170 C. X32(1/70)31,X3170 D. X32M3Y3,X3170Y3 X2 for the X2 discount and 70 units of X3 for the X3 discount. How many binary variables are required in the formulation of this problem? A. 3 B. 6 C. 9 D. 12