please help me to solve this problem and please do all required journal entry.

Ernst Company purchased equipment that cost $3,000,000 on January 1,2020 . The entire cost was recorded as an expense. The equipment had a nine-year life and a $120,000 salvage value. Ernst uses the straight-line method to account for depreciation expense. The error was discovered on December 10, 2022. Ernst is subject to a 20% tax rate. Required: 1. By how much was the Ernst's net income for the year ended December 31,2020 , understated? 2. Prepare all required journal entry in 2022