please i need the solution of a and b

At the end of 2016, waterway Industries has accounts receivable of $727, 400 and an allowance for doubtful accounts of $27.280. On January 24, 2017, it is learned that the company's receivable from Madonna Inc. is not collectible and therefore management authorized a write-off of $4, 480. (a) Prepare the journal entry to record the write-off. (Credit account titles are automatically indented when amount is entered. Do not indent manually.) (b) What is the cash realizable value of the accounts receivable before the write-off and after the write off? Cash realizable value $ =