On January 1, 2022, a company purchased a new machine for $100,000. The machine has an estimated useful life of 5 years and an estimated residual value of $10,000. The company uses the straight-line method to depreciate its assets. On December 31, 2022, the company decides to change its estimate of the machine's useful life to 4 years and its estimated residual value to $8,000.

a) Calculate the annual depreciation expense for 2022, assuming the original estimates of useful life and residual value were used.
b) Calculate the carrying value of the machine on December 31, 2022, assuming the original estimates of useful life and residual value were used.
c) Calculate the revised annual depreciation expense for 2022, assuming the revised estimates of useful life and residual value are used.
d) Calculate the carrying value of the machine on December 31, 2022, assuming the revised estimates of useful life and residual value are used.
e) Prepare the adjusting journal entry to record the revised depreciation expense as of December 31, 2022.