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QUESTION-3 Your local grocery store stocks facial tissue in single packages and in more economi- cal 12-packs. You are trying to decide which to buy. The single package costs 45 cents, and the 12-pack costs $5. You consume tissues at a fairly steady rate of one pack every three months. Your opportunity cost of money is computed assuming an interest rate of 25 percent and a fixed cost of $1 for the additional time it takes you to buy bathroom tissue when you go shopping. (We are assuming that you shop often enough so that you don't require a special trip when you run out.) a) How many single packages should you be buying in order to minimize the annual holding and setup costs of purchasing tissues? b) Determine if it is more economical to purchase the tissues in 12-packs