Weekly demand for cell phones is normally distributed with an average of 250 and a standard deviation of 150 . The store manager has decided to follow a periodic review policy to manage the inventory of cell phones. They plan to review inventory and order every three weeks. The manufacturer currently takes two weeks to fill an order. Given a desired CSL of 95%, how much safety stock inventory should the store carry? Round your answer to the nearest whole number. Note: CSL= customer service level