Use Solver to create a Sensitivity Report for question 15 at the end of Chapter 3, and answer the following questions:
a. Is the solution degenerate?
b. Is the solution unique?
c. Explain the signs of the reduced costs for each of the decision variables. That is, considering the optimal value of each decision variable, why does the sign of its associated reduced cost make economic sense?
d. Suppose the cost per pound for Feed 3 increased by $3. Would the optimal solution change? Would the optimal objective function value change?
e. If the company could reduce any of the nutrient requirements, which one should it choose and why?
f. If the company could increase any of the nutrient requirements, which one should it choose and why?
g. Suppose there is some uncertainty about the cost estimates for each type of feed. Prepare a Spider Plot varying the cost per pound of each feed type between plus and minus $0.25 of its stated value in $0.05 increments and tracking the impact on the optimal cost. What does this chart reveal, and what are the managerial implications?