Determine the amount to be added to Allowance for Doubtful Accounts in each of the following cases and indicate the ending balance in each case. a. Credit balance of $330 in Allowance for Doubtful Accounts just prior to adjustment. Using the aging method, the balance of Allowance for Doubtful Accounts is estimated as $7,700. Amount added Ending balance 7,370 7,700 b. Credit balance of $330 in Allowance for Doubtful Accounts just prior to adjustment. Bad debt expense is estimated at 1% of credit sales, which totaled $826,000 for the year. Amount added Ending balance 8,260 8,590.