I need help with the last part, I cannot figure it out please explain.

Required information (The following information applies to the questions displayed below) A company has the following transactions during May May 2 Purchases books on account from Readers Wholesale for $2,500, terms 2/18, n/30. May 3 Pays cash for freight costs of $12e on books purchased from Readers. May 5 Returns books with a cost of $250 to Readers because part of the order is incorrect May 10 Pays the full amount due to Readers. May 30 sells all books purchased on May 2 (less those returned on May 5) for $3,200 on account. Required: 1. Record the transactions of the company, assuming the company uses a periodic inventory system. (If no entry is required for a transaction/event, select "No Journal Entry Required" in the first account field.) Required information No General Journal Credit Date May 02 Debit 2,500 1 Purchases > Accounts Payable 2,500 2 May 03 120 Freight-in Cash 120 3 May 05 250 Accounts Payable Purchase Returns 250 4 May 10 2,250 Accounts Payable Cash Purchase Discounts 2,205 45 5 May 30 Accounts Receivable Sales Revenue 3200 3.200 . 6 May 30 Cost of Goods Sold Sales Rovenue 3,200 $ X 3,200 Required information Journal entry worksheet 3 5 6 Record cost of inventory sold. Note: Enter debits before credits. Date General Journal Debit Credit May 30 Record entry Clear entry View general journal