At the end of the current year, the accounts receivable account has a debit balance of $1,006,000 and sales for the year total $11,410,000. The allowance account before adjustment has a debit balance of $13,600. Bad debt expense is estimated at 3/4 of 1% of sales. The allowance account before adjustment has a debit balance of $13,600. An aging of the accounts in the customer ledger indicates estimated doubtful accounts of $43,500. The allowance account before adjustment has a credit balance of $8,700. Bad debt expense is estimated at 1/4 of 1% of sales. The allowance account before adjustment has a credit balance of $8,700. An aging of the accounts in the customer ledger indicates estimated doubtful accounts of $72,200. Determine the amount of the adjusting entry to provide for doubtful accounts under each of the assumptions (a through d) listed above.