How to you get the straight line, units of activity, and Double declining method?

Skysong. Inc, purchased a delivery truck for $30,000 on January 1, 2022. The truck has an expected salvage value of $4,000, and is eqected to be driven 100,000 miles over its estimated useful life of 8 years. Actual miles driven were 14,800 in 2022 and 15,000 in 2033 Compute depreciation expense for 2022 and 2023 using (1) the straight-line method, (2) the units-of-activity method, and (3) the double-declining-balance method