please explain how to do this

The Heritage Company has provided the following information: Allowance for doubtful accounts increased $25,000 and accounts receiv increased $400,000 during the year. Accounts written off as uncollectible totaled $10,000. divissa Net sales totaled $3,250,000. Sales discounts were $90,000. The gross profit percentage was 30%. How much was Heritage's bad debt expense? A. $ 90,000 B. $ 35,000 C. $125,000 D. $ 55,000 E. None of the above