why is the $150 and the 2% not included on anything?

Echo Company started the year with a $4,600 balance in accounts receivable and a $150 balance in the allowance for doubtful accounts. The company had credit sales of $12,000, and collections on accounts receivable of $13,000. The company believes that 2 percent of its credit sales will be uncollectible 2. The balance in the accounts receivable account at the end of the year would be a. $3.400 Accounts Receivable b. $3,600 Beginning Balance 4.600 CS3.250 Sales on account 12.000 d. $4.360 Cash collectioned 13.000 Balance 3.600