The following items were extracted from the 2008 financial records of Cummins, Inc. (dollars in millions):

Allowance for doubtful accounts 12 (cr.)

During the following year, the company wrote off $11 of accounts receivable as uncollectible and then estimated $9 of the year’s receivables to be uncollectible. The company did not recover any previously written-off accounts.

a. Prepare the entry to record the bad debt expense.

b. Compute the final baalance in allowance for doubtful accounts.