When originally purchased, a vehicle had an estimated useful life of 8 years. The vehicle cost $25,000 and its estimated residual value is $3,000. After 3 years of straight-line depreciation, the asset's total estimated useful life was revised from 8 years to 5 years and there was no change in the estimated residual value. The Depreciation Expense in year 4 is: A) $6,875 B) $4,400 C) $4,125 D) $1,650 Explain your selected answer in detail. Show all the steps of the correct answer, including the formula used.