A small restaurant uses 100 compostable food containers for their to-go orders every week. Placing an order to re-stock the food container inventory has a cost of $4, and holding one container in inventory for a year has a cost of $1. Assume that: an order is placed once the inventory is depleted, the lead time to receive the order once it's placed is negligible, and that a year has 50 weeks. If the food container supplier only ships boxes of 25 units, how many boxes should be ordered every time the food container inventory is re-stocked to minimize the total annual cost? Your answer should be an integer number