A chef locates a pre-made tuna salad that is nearly identical to the one she makes from scratch in her sandwich shop. To make it from scratch, an $14.50/hour employee needs 30 minutes to prepare the tuna salad. The ingredients cost $17.15 and yield 12 four-ounce servings. The chef can purchase the pre-made tuna salad at $35.00 for a 5# tub. Calculate the cost per portion for the scratch-made and the premade versions. If cost were the only factor, should the chef make or buy this product