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 resells it to farmers who use it to feed their animals. This week the supermarket can buy fresh lettuce for $6.00 a box. The lettuce is sold for $18.00 a box and the dealer that sells old lettuce is willing to pay $3.60 a box. Past history says that tomorrow's demand for lettuce averages 254 boxes with a standard deviation of 37 boxes. How many boxes of lettuce should the supermarket purchase tomorrow? (Use Excel's NORMSINV() function to find the Z-score. Round intermediate calculations to four decimal places. Round your answer to the nearest whole number.) Number of boxes

You are thinking of making your mansion more energy efficient by replacing some of the light bulbs with compact fluorescent bulbs, and insulating part or all of your exterior walls. each compact fluorescent light bulb costs $4 and saves you an average of $2 per year in energy costs, and each square foot of wall insulation costs $1 and saves you an average of $0.20 per year in energy costs.† your mansion has 150 light fittings and 3000 sq ft of uninsulated exterior wall. to impress your friends, you would like to spend as much as possible, but save no more than $750 per year in energy costs (you are proud of your large utility bills). how many compact fluorescent light bulbs and how many square feet of insulation should you purchase? how much will you save in energy costs per year? (if an answer does not exist, enter dne.)