A small firm makes similar products, which all follow the same three-step process, consisting of milling, inspection, and drilling. Product A requires 12 minutes of milling, 5 minutes for inspection, and 10 minutes of drilling per unit. Product B requires 10 minutes of milling, 4 minutes for inspection, and 8 minutes of drilling per unit. Product C requires 8 minutes of milling, 4 minutes for inspection, and 16 minutes of drilling. The firm has 20 hours available during the next period for milling, 15 hours for inspection, and 24 hours for drilling. Product A contributes $3.40 per unit to profit, product B - $2.00 per unit, and product C - $2.50. Determine the optimal mix of products in terms of maximizing contribution to profits. Make sure to provide an appropriate integer solution. Please attach your original Excel or R file with your name and date