On December 31, 2017, Bruce Corporation had the following account balances related to credit sales and receivables prior to recording adjusting entries: Accounts receivable $168,000 Allowance for doubtful accounts 700 credit balance Sales revenue (all credit sales) 550,000 Required: Prepare the necessary year-end adjusting entry related to uncollectible accounts for each of the following independent assumptions: A. On December 31 an Accounts Receivable (Jane Doe) of $300 from a prior year was determined to be uncollectible; therefore, it was written off immediately as a bad debt. B. It is estimated that a provision for bad debts is required for 1% of credit sales for the year. C. An aging of accounts receivable is completed. It is estimated that $6,000 of the receivables outstanding at year-end will be uncollectible.