A company purchased a piece of equipment for $30,000 on January 1, 2019. Management estimates residual value of $4,000 and a useful life of four years. It uses the straight-line method of depreciation. Where applicable, it applies the half- year rule. On January 1, 2021, management estimates the remaining useful life to be four years and the new residual value to be $3,000. What is the annual depreciation expense for 2019? $4,800 $3,250 $6,500 $5,200