Include the excel solution of an LP problem. Question 4. A farmer blends two brands Pera and Qorte of sheep feed. Pera costs $250 per bag and contains 3 units of nutritional element Ad, 2.5 units of element Bod and 2 units of element Cad. Qorte costs $200 per bag and contains 1.5 units of Ad, 11.25 units of Bod, and 3 units of Cad. To ensure proper nutrition and to make sure that the farming practices meet government regulations, the farmer has to feed the sheep with at least 18 units of Ad, 45 units of Bod and 24 units of Cad per day. You will formulate and solve a linear programming model to help the farmer determine the optimal mix of bags of each brand (i.e., quantity of bags of each type to buy in order to minimize the total cost) to feed the sheep on a particular day. Assume no feed was left in stock from the previous day. NOTE: SHOW ALL YOUR WORK. a) (3 points) What are the decision variables? How many decision variables are there? Clearly explain the decision variables in English and provide the mathematical notation used in the algebraic formulation of the decision problem. b) (2 points) What is the objective function? Clearly explain the objective function in English and provide the mathematical formulation. c) (2 points) What are the constraints of the problem? Clearly explain each constraint in English and provide the mathematical formulation. d) (1 points) Are there any sign or type restrictions in your formulation? Why or why not? Clearly explain the sign and type restrictions (if any). e) Prepare a spreadsheet to determine the optimal production mix of using Excel Solver. i. (2 points) Provide a screenshot of your spreadsheet model. The screenshot should show all the cells involved in formulating the optimization problem. NOTE: Do not copy and paste your spreadsheet to your answer report as an Excel object. Instead, capture a screenshot in Excel and paste this as an image. ii. (2 points) Provide a screenshot of your spreadsheet with the formula view. You can switch from normal view to formula view in Excel by clicking the CTRL and ~ keys on your keyboard simultaneously. iii. (2 points) Prepare the Solver model by logging all the information to the Solver Parameters window in Excel. Provide a screenshot of the Solver Parameters window. iv. (2 points) Solve the optimization problem using Excel Solver. What is the optimal solution, i.e. the optimal values of the objective function and the decision variables?