Assume that Simple Company had credit sales of $$282,000$ and cost of goods sold of $$166,000$ for the period. It estimates that $1$ percent of credit sales in uncollectible accounts when it uses the percentage of credit sales method and it estimates that the appropriate ending balance in the Allowance for Doubtful Accounts is $$3,900$ when it uses the aging method. Before the end$-$of$-$period adjustment is made, the Allowance for Doubtful Accounts has a credit balance of $$410.$

Required:

Prepare the journal entry to record the end$-$of$-$period adjustment for bad debts under the $($a$)$ percentage of credit sales method and $($b$)$ aging of accounts receivable method.

Which of these methods is required by GAAP?