A museum of natural history opened a gift shop two years ago. Managing inventories has become a problem. One of the top selling units at the museum$$s gift shop is a bird feeder. Sales are $18$ units per week, and the supplier charges $$60$ per unit. The cost of placing an order with the supplier is $$45.$ Annual holding cost is $25\%$ of a feeder$$s value, and the museum operates $52$ weeks per year.

b$.$ Calculate the EOQ. Round up to the whole number.

$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ units

Please write just the numbers.