Apex, Inc. has a number of plant \& equipment assets that it wishes to calculate the 2019 and 2020 depreciation expense for, as follows: 1. The company purchased a machine on April 1, 2019 for a cost of $24,000. Apex estimates its useful life to be five years, and its salvage value to be $4,000. Apex uses the straight-line method of depreciation on this machine. 2. Equipment was purchased on March 1, 2018 at a cost of $30,000. Apex uses the sum-of-theyears-digits method to record depreciation on the equipment. The useful life is estimated to be 4 years, and the salvage value is estimated at $2,000. 3. Apex purchased a new machine on January 1, 2018 at a cost of $44,000. At that time Apex used the double-declining balance method of depreciation, estimated the asset's life at 10 years, and its salvage value at $4,000. On January 1, 2020, Apex decides to change to the straight-line method for this asset, and also changes its remaining useful life (as of January 1,2020) to ten years. 4. Apex purchased a new automobile on January 1, 2018 at a cost of $35,000. It estimated the auto's life at 100,000 miles, and its salvage value at $5,000. During 2018 the auto was driven a total of 20,000 miles. On January 1, 2019, Apex decided to change the salvage value of the auto to $2,000, beginning on that date. The total original estimated life of 100,000 miles was not changed. The auto was driven a total of 30,000 miles both in 2019 and 2020. 5. A machine was purchased on September 1,2019 at a cost of $20,000. Its life was estimated at 5 years, and salvage value was estimated at $2,000. Apex uses the double-declining balance method of depreciation for this asset. On January 1, 2020, Apex decided to change the asset's salvage value to $5,000