The balance sheet of Antonio Vivaldi Company at December 31, 2007, includes the following. Transactions in 2008 include the following. 1. Accounts receivable of $ 138,000 were collected including accounts of $40,000 on which 2% sales discounts were allowed. 2. $6, 300 was received in payment of an account which was written off the books as worthless earlier in 2008. 3. Customer accounts of $ 17, 500 were written off during the year. 4. At year-end the Allowance for Doubtful Accounts was estimated to need a balance of $20,000. This estimate is based on an analysis of aged accounts receivable. Prepare all journal entries necessary to reflect the transactions above