Grouper Company purchased a delivery truck for $33,000 on January 1, 2020. The truck has an expected salvage value of $1,390, and is expected to be driven 109,000 miles over its estimated useful life of 10 years. Actual miles driven were 15,400 in 2020 and 12,500 in 2021. (a1) (a2) Compute depreciation expense for 2020 and 2021 using (1) the straight-line method, (2) the units-of-activity method, and (3) the double-declining-balance method. (Round depreciation cost per unit to 2 decimal places, e.g. 0.50 and depreciation rate to 0 decimal places, e.g. 15%. Round final answers to 0 decimal places, e.g. 2,125.) Depreciation Expense 2020 2021 (1) Straight-line method $ $ (2) Units-of-activity method $ $ (3) Declining-balance method $ $