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Riverbed Corporation sells one product, with information for July as follows: July 1 Inventory 100 units at $16.00 each 4 Sale 80 units at $20.00 each 11 Purchase 150 units at $16.40 each 13 Sale 120 units at $18.80 each 20 Purchase 160 units at $16.40 each 27 Sale 100 units at $20.90 each Riverbed uses the FIFO cost formula. All purchases and sales are on account. Ignore any estimated returns on purchases and sales. (a) Assume Riverbed uses a periodic system. Prepare all journal entries needed, including the end-of-month adjusting entry to record cost of goods sold. A physical count indicates that the ending inventory for July is 110 units. (Credit account titles are automatically indented when the amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter O for the amounts. Record journal entries in the order presented in the problem.) Date Account Titles and Explanation Debit Credit July 31