Northern Distributors is a wholesale organization that supplies retail stores with lawn care and household products. One building is used to store Neverfail lawn mowers. The building is 25 feet wide by 40 feet deep by 8 feet high. Anna Oldham, manager of the warehouse, estimates that about 60% of the warehouse can be used to store the Neverfail lawn mowers. The remaining 40% is used for walkways and a small office. Each Neverfail lawn mower comes in a box that is 5 feet by 4 feet by 2 feet high. The annual demand for these lawn mowers is 12,000 and the ordering cost for Northern Distributors is $30 per order. It is estimated that it cost Northern $2 per lawn mower per year for storage. Northern distribution is thinking about increasing the size of the warehouse. The company can only do this by making the warehouse deeper. At the present time, the warehouse is 40 feet deep. How many feet of depth should be added on the warehouse to minimize the annual inventory costs? How much should the company be willing to pay for this addition? Remember that only 60% of the total area can be used to store Neverfail lawn mowers. Assume all EOQ conditions are met.