Recording Entry for a Change in Estimate Exon Company purchased equipment for $180,000 on January 1 of Year 1 . The equipment has an estimated residual value of $5,400 and an estimated useful life of 8 years. The company depreciates the equipment using the straight-line method. On January 1 of Year 4, the company determines that the total useful life is 6 years and the estimated residual value is $1,800. Required