Pessimist Inc The Balance of the Allowance for Doubtful Accounts as of the Years

Pessimist Inc. reported credit sales of $5,400,000 and $4,800,000 for the years ended December 31, 2020 and 2021, respectively. Information on trade accounts receivable for the company is presented below.
$$\begin{array} { l r r r r } \text { Days outstanding } & \text { Current } & \text { 31-60 } & \mathbf { 6 1 - 9 0 } & \text { 91+ } \\\text { Balance in A/R. Dec. 31. 2020 } & 397,000 & 156,000 & 47,000 & 17,000 \\\text { Balance in A/R. Dec. 31. 2021 } & 392,000 & 141,000 & 33,000 & 26,000 \\\% \text { of AR est. to be uncollectible } & 0.8 \% & 5.0 \% & 6.0 \% & 9.0 \%\end{array}$$ The balance of the allowance for doubtful accounts as of January 1, 2020 was $15,000. In addition, you learn that the company wrote off specific accounts of $18,500 in 2020, and the bad debts expense was $13,000 in 2021.
Required:
a. Determine the bad debts expense for 2020.
b. Determine the amount of receivables written off during 2021.
c. Prepare the journal entry to record the bad debts expense for 2020.