Blackhorse Productions, Inc., used the aging of accounts receivable method to estimate that its Allowance for Doubtful Accounts should be $21,550. The account had an unadjusted credit balance of $10,900 at that time.

a. The appropriate bad debt adjustment was recorded.
b. Later, an account receivable for $1,900 was determined to be uncollectible and was written off.

Required:
For each transaction listed above, indicate the amount and direction for increase or-for decrease) of effects on the financial statement accounts and on the overall accounting equation.