A Drug manufacturing company produces three types of drugs (A, B, and C). The company uses two types of ingredients (I and II), of which 4000 and 6000 grams are available, respectively. The ingredient requirements per unit of the three drugs are as follows: Ingredient I II Requirements per Unit of A 20 50 Requirements per Unit of B 33 20 Requirements per Unit of C 50 60 The machine-hour required for each unit of drug A is twice of that of drug B and three times of that of drug C. The entire machine-hour available in the factory is enough to produce the equivalent of 1500 units of Drug A. A market survey indicates that the minimum demand for three drugs is 300, 400, and 250 units, respectively. However, the ratios of the number of units produced must be equal to 2:1:3, respectively. Assume that the profit per unit of drugs A, B, and C is $40, $30, and $60, respectively. Formulate the problem as an LP model to determine the number of units of each product that will maximize the profit. Important: You are asked only to formulate the problem; you are not asked to solve the problem. Indicate your decision variables as XA, XB, and Xc as the number of units to be produced of drugs A, B, and C, respectively. In your formulation, follow the give steps below. a) The objective function: b) Constraint(s) for raw material usage: c) Machine-hour constraint(s): d) Demand constraint(s): e) Constraint(s) on relative production amounts: f) Non negativity constraint(s):