Raturi Chemicals Inc., produces four industrial chemi-cals with variable production costs of $9.00, $6.75, $5.25, and $7.50 per pound, respectively. Because of increasing supplier costs, the variable cost of each of the products will increase by 6% at the beginning of month 3. Demand forecasts are shown in the fol-lowing table. There are currently 100 pounds of each product on hand, and company wants to maintain an inventory of 100 pounds of each product at the end of every month. The four products share a common pro-cess that operates two shifts of 8 hours each per day, 7 days per week. Processing requirements are 0.06 hours/pound for product 1, 0.05 hours/pound for prod-uct 2, 0.2 hours/pound for product 3, and 0.11 hours/pound for product 4. The per-pound cost of holding inventory each month is estimated to be 12% of the cost of the product. Develop an optimization model to meet demand and minimize the total cost. Assume 30 days per month. Implement your model on a spread-sheet and find an optimal solution with Solver.

Product Demand
Product	Month 1	Month 2	Month 3
1	1,000	800	1,000
2	1,000	900	500
3	600	600	500
4	0	200	500