Happy's Mechanic Shop uses the Aging-of-Receivables method to estimate uncollectible amounts. For 2021, Happy aged her Accounts Receivable balance and estimated uncollectible account percentages as follows: A/R balance % uncollectible 1-30 days past Currently Due 31+ days past due Total A/R due $80,000 1% $8,000 $5,000 $93,000 15% 40% At December 31, 2021, the unadjusted balance in the Allowance for Doubtful Accounts is a $1,200 credit. On March 1, 2022, the credit manager authorizes a write-off of the $1,000 balance owed by W. O'Brien, one of their customers. Complete the following: (a) Prepare the adjusting entry to record the estimated uncollectible amount in 2021for Happy. (b) Make the appropriate journal entry to record the write-off of the O'Brien account in 2021. (c) Happy uses the Aging-of-Receivables method. What would the ending balance be in Happy's Allowance for Doubtful Accounts after the write-off on March 2, 2022