The florist section stocks 40 dozen roses at the beginning of each week. These roses are sold only by dozen. On average, the florist sells 8 dozens a day, but the actual demand follows a Poisson distribution. Whenever the stock level reaches 10 dozens, a new order of 40 new dozens is placed for delivery at the beginning of the following week. Because of the nature of the item, all roses left at the end of the week are disposed of. Determine the following:

1. The probability that the stock is depleted before the 4^th day of the week.
2. The probability that no order will be placed by the end of the week (Hy-Vee opens 7days/week)
3. The average number of dozen roses that will be discarded at the end of the week (Need excel)