The local supermarket buys lettuce each day to ensure really fresh produce. Each morning any lettuce that is left from the previous day is sold to a dealer that it resells to farmers who use it to feed their animals. This week the supermarket can buy fresh lettuce for $4.00 a box. The lettuce is sold for $10.00 a box and the dealer that sells old lettuce is willing to pay $1.50 a box. Past history says that tomorrows demand for lettuce averages 250 boxes with a standard deviation of 34 boxes. How many boxes of lettuce should the supermarket purchase tomorrow? (Assume that the demand is normally distributed.)

• Start with identification of Cu and Co IN THE CONTEXT OF THE PROBLEM. Clearly explain how the Cu and Co numbers are chosen.
• Compute the service level based on Cu and Co
• Identify the mean, standard deviation; compute z and the perfect order
• Offer a pictorial view of the distribution, the perfect order point, and the service level on the side, so that it is easy to understand.