6. Plain Company began the operation in 2020. Information about the ending inventories of the Plain Company is shown below: Required: (16 points) a. Assuming a perpetual inventory system, prepare journal entries for 2020, 2021, 2022 to record the reduction of the inventory to market value using the loss-allowance method. b. Assuming a perpetual inventory system, prepare journal entries for 2020,2021,2022 to record the reduction of the inventory to market value using the cost of goods sold-inventory method