A battery distributor manages their inventory of AAA batteries using a periodic review system. The review period is set to 4 days, and the order-up-to level is 15,000 units. Today is the day to place an order; currently, there is no onhand inventory. Additionally, there are 8,000 units of inventory on order and 1,000 units in backorders. What should be the order quantity for this period? 7,0008,0009,00014,000