Not sure what I am missing here. Please help. TYIA.

PA8-2 (Algo) Interpreting Disclosure of Allowance for Doubtful Accounts [LO 8-2] Marshall Travel, disclosed the following rounded amounts (in millions) concerning the Allowance for Doubtful Accounts on its Form 10K annual report. Required: 1-a. Prepare a T-account for the Allowance for Doubtful Accounts and enter into it the 2016 amounts from the above schedule. The balance at the beginning of each year in the Allowance for Doubtful Accounts is a credit balance. 1-b. Write the T-account in equation format to prove the above items account for the changes in the account. 2. Record summary journal entries for 2017 related to (a) estimating Bad Debt Expense and (b) writing off specific customer account balances. 3. Supply the missing information for 2018. 4. If Marshall Travel had written off an additional $23 of Accounts Receivable during 2018 , by how much would Net Receivables have decreased? How much would Net Income have decreased? Answer is not complete. Complete this question by entering your answers in the tabs below. Write the T-account in equation format to prove the above items account for the changes in the account. (Enter your answers in millions.)