Repeat M7-8, except assume Literacy for the Illiterate uses a perpetual inventory system and it sold 600 units between January 9 and January 28. 

Data From  M7-8.

In its first month of operations, Literacy for the Illiterate opened a new bookstore and bought merchandise in the following order: (1) 300 units at $7 on January 1, (2) 450 units at $8 on January 8, and (3) 750 units at $9 on January 29. Assuming 900 units are on hand at the end of the month, calculate the cost of goods available for sale, ending inventory, and cost of goods sold under the (a)  FIFO and (b) weighted average cost flow assumptions. Assume a periodic inventory system is used.