The Black Jack Distillery produces custom-blended whiskey. A particular blend consists of rye and bourbon whiskey. The company has received an order for a minimum of 400 liters of the custom blend. The customer specified that the order must contain at least 40% rye and not more than 250 liters of bourbon. The customer also specified that the blend should be mixed in the ratio of two parts rye to one part bourbon. The distillery can produce 500 liters per week, regardless of the blend. The production manager wants to complete the order in one week. The blend is sold for $12 per liter. The distillery company’s cost per gallon is $4 for rye and $2 for bourbon. The company wants to determine the blend mix that will meet customer requirements and maximize profits. 

a.  Formulate and solve a linear programming model for this problem.
b.  Solve the problem using the graphical method.