Required: Prepare journal entries for each transaction listed. (If no entry Is required for a transaction/event, select "No Journal Entry Required" in the first account field.) a. At the end of June, bad debt expense is estimated to be $13,200 : b. In July, customer balances are written off in the amount of $6,600. Journal entry worksheet Record the customer balances written off in the amount of $6,600. Note: Enter debits before credits