Sunnyside Marine Products began the year with 10 units of marine fl oats at a cost of $11 each. During the year, it made the following purchases: May 5, 30 unit at $16; July 16, 15 units at $19; and December 7, 20 units at $23. Assuming there are 25 units on hand at the end of the period, determine the cost of goods sold under (a) FIFO, (b) LIFO, and (c) average-cost. Sunnyside uses the periodic approach.