The accountant for Birdwell Enterprises uses the income statement approach to estimate bad debt expenses. Birdwell's annual sales were $400,000. The firm's accounts receivable balance is $100,000. Uncollectible accounts are accruing at a rate of 3% of total sales. What is the estimated bad debts expense for Birdwell?

a. $ 9,000

b. $ 3,000

c. $15,000

d. $12,000