What are the journal entries?

Super Copy Co. is an office supply store. The company uses a perpetual inventory system, records purchases at net cost, and records sales revenue at full invoice price. Record the following transactions in the company's general journal. To conserve space, omit the written explanations which normally should accompany the entries. July 1 Purchased four Doni copying machines on account from Doni Corp. Total invoice price was $4,000 per machine ($16,000 total); terms of 2/10, n/30. These machines are intended for resale. 3 Found one of the Doni copiers to be defective and returned it to Doni, thus reducing the amount owed. 9 Sold one of the Doni copiers to Cross Realty. The sales price was $5,000, terms 5/10, n/60. 10 Paid the remaining amount owed to Doni Corp., less the allowable discount. 19 Received full payment from Cross, less the allowable discount