Demand for long-stemmed red roses at a small flower shop can be approximated using a normal distribution with mean 25 dozen per day and a standard deviation of 2.5 dozen per day. Profit on the roses is $5.00 per dozen. Leftover flowers are marked down and sold the next day at a loss of $2.00 per dozen (assume that all marked-down flowers are sold). What is the optimal daily stocking level?