Mountain View Resorts purchased equipment at the beginning of 2021 for $33,000. Residual value at the end of an estimated four-year service life is expected to be $7,200. The machine operated for 1,800 hours in the first year and the company expects the machine to operate for a total of 12,000 hours over its four-year life. Calculate depreciation expense for 2021, using each of the following depreciation methods: (1) straight-line, (2) double- declining-balance, and (3) activity-based. (Round your intermediate calculations to 2 decimal places.) Depreciation Expense Straight-line Double-declining-balance Activity-based