At each calendar year-end, Mazie Supply Co. uses the percent of accounts receivable method to estimate bad debts. On December 31, 2016, it has outstanding accounts receivable of $90,500, and it estimates that 4% will be uncollectible. Prepare the adjusting entry to record bad debts expense for year 2016 under the assumption that the Allowance for Doubtful Accounts has: (a) a $1,539 credit balance before the adjustment. (b) a $453 debit balance before the adjustment.