In its first month of operations, Waterway Industries made three purchases of merchandise in the following sequence: (1) 370 units at $4, (2) 470 units at $6, and (3) 570 units at $7. Assuming there are 270 units on hand at the end of the period, compute the cost of the ending inventory under (a) the FIFO method and (b) the LIFO methis. Waterway Industries uses a periodic inventory system