help with both please!

Net credit sales for the month are $900,000. The accounts receivable balance is $192,000. The allowance is calculated as 5% of the receivables balance using the percentage-of-receivables basis. If the Allowance for Doubtful Accounts has a credit balance of $6,000 before adjustment, what is the balance after adjustment? $15,600 $ 3,600 $ 9,900 $ 9,600 Under GAAP, companies can choose which inventory cost flow assumptions? LIFO FIFO Yes No No No Yes Yes No Yes