Burnaby Corp. uses the revenue approach to account for warranties. During 2020, the company sold $ 780,000 worth of products, all of which carried a two-year warranty (included in the price). It was estimated that 2% of the selling price represented the warranty portion, and that 40% of this related to 2020, and 60% to 2021. Assuming that Burnaby incurred costs of $ 2,500 to service the warranties in 2020, and $5,800. What is the balance in the Unearned Warranty Revenue account at the end of 2020?

O a. (78*200)-2500

O b. ((78*10000)*0.4)-2500

O c. 2500

O d. (78*200)*0.6