Please answer Questions 4 and 5. Thank you!

Zhongli Company sells directly to customers. On January 1, 2021, the balance of accounts receivable ledger is P250,000 and the allowance for doubtful accounts has a credit balance of P20,000. The following data are available since 2018: Credit Sales Writeoff Recoveries 2018 1,100,000 26,000 2,000 2019 1,200,000 29,000 3,000 2020 1,500,000 30,000 4,000 2021 3,000,000 40,000 5,000 Doubtful accounts are provided for as a percentage of credit sales. The accountant calculates the percentage annually by using the experience of the three years prior to the current year. The formula is accounts written off less recoveries expressed as a percentage of the credit sales. Cash receipts in 2020 from credit sales including recoveries amounted to P2,615,000. QUESTION 1: What is the percentage to be used in computing the allowance for doubtful accounts on December 31, 2021? Hint: use totals, not average. QUESTION 2: How much is the doubtful accounts expense for 2021? QUESTION 3: What is the ledger balance of accounts receivable on December 31, 2021? QUESTION 4: What is the ledger balance of the allowance for doubtful accounts after necessary adjustments on December 31, 2021