Albatross Company purchased a piece of machinery for $60,000 on January 1, 2019 and has been depreciating the machine using double declining method balance based on a five year estimated useful life and no salvage value. On January 1, 2021, Albatross decided to switch to the straight line method of depreciation. Ignore income taxes in calculations.

a Prepare the appropriate journal entry, if any, to record the accounting change.

b Prepare the journal entry to record depreciation for 2021.

c Because of a mistake in computing depreciation expense, Albatross Company overstated its depreciation expense. It recorded $20 million of depreciation expense in 2019 and $20 million of depreciation expense in 2020. The actual depreciation expense should have been $10 million annually. Albatross Company's auditor discovered this error in 2021. Prepare the adjusting journal entry on December 31, 2021 to correct the error.