Kingbird, Inc. began the year with 10 units of marine floats at a cost of $11 each. During the year, it made the following purchases: May 5, 35 unit at $17; July 16, 15 units at $21; and December 7, 20 units at $25. Assume there are 25 units on hand at the end of the period. Kingbird uses the periodic approach. Determine the cost of goods sold under average-cost.