only need solution! know how to do but dont have time

We use a Periodic Review system to manage an inventory item for which demand averages 110 units a week with a standard deviation of 14 units. Lead time for this item is 2 units and our order interval is 9 weeks. Our policy is to manage our inventory such that we run not more than a 2.5% risk of a stockout. Suppose we are about to place an order for this item and have determined that our on-hand inventory is 400 units. What should our order quantity be? (Round to 2 decimal places and report only the number.)