i cant figure out the last one number 8. can i please have a explanation of answer. the rest is 100% correct

thanks

The following information applies to the questions displayed below The following events occur for The Underwood Corporation during 2018 and 2019, its first two years of operations. June 12, 2018 Provide services to customers on account for $31,400. September 17, 2018 Receive $17,000 from customers on account. December 31, 2018 Estimate that 40% of accounts receivable at the end of the year will not be received. March 4, 2019 Provide services to customers on account for $46,400 May 20, 2019 Receive $10,000 from customers for services provided in 2018. July 2, 2019 Write off the remaining amounts owed from services provided in 2018 October 19, 2019 Receive $37,000 from customers for services provided in 2019. December 31, 2019 Estimate that 40% of accounts receivable at the end of the year will not be received. value: 2.50 points Required 1. Record transactions for each date. (If no entry is required for a transaction/event, select "No journal entry required" in the first account field.) View transaction list View journal entry worksheet No Date General Journal Debit Credit 1June 12, 2018Accounts receivable 31,400 Service revenue 31,400 2Setmer 7 Caslh 17,000 2018 Accounts receivable 17,000 December 31, 2018 Bad debt expense 5,760 Allowance for u e accounts 5,760 2 4 March 04, 2019 Accounts receivable 46,400 Service revenue 46.400 2 May 20, 2019 Cash 10,000 Accounts receivable 10,000 6 July 02, 2019 Allowance for uncollectible accounts 4,400 Accounts receivable 4,400 7 October 19, 2019 Cash 37,000 Accounts receivable 37,000 December 31, 2019 Bad debt expense Allowance for uncollectible accounts