Below is the net income of Vaughn Instrument Co,a private corporation, computed under the three inventory methods using a periodicsystem. (lgnore taxconsiderations) ta) Assume that in 2021 Vaughin decided to change from the FIFO method to the average-cost method of pricing inventories. Prepare the fournal entry necessary for the change that took place during 2021. and show net income reported for 2018, 2019. 2020, and 2021. (Credit account tities are automatically indented when amount is entered. Do not indent manually if no entry is required, select "No Entry for the occount titles and enter ofor the anounts.) (b) Assume that in 2021 Vaughn, which had been using the UFO method since incorporation in 2018 , changed to the FIFO method of pricing imentories. Prepare the journal entry necessary to record the change in 2021 and show net income reported for 2018,2019. 2020, and 2021. (Credit occount titles are outomatically indented when amount is entered, Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter O for the amounts.)