Can you please help with this problem, and give an explanation for the correct answer? Thank you

A machine costing $210,400 with a four-year life and an estimated $18,000 salvage value is installed in Luther Company's factory on January 1. The factory manager estimates the machine will produce 481,000 units of product during its life. It actually produces the following units: 122,100 in 1st year, 123,500 in 2nd year, 120,600 in 3rd year, 124,800 in 4th year. The total number of units produced by the end of year 4 exceeds the original estimate-this difference was not predicted. (The machine must not be depreciated below its estimated salvage value.) Required: Compute depreciation for each year (and total depreciation of all years combined) for the machine under each depreciation method. (Round your per unit depreciation to 2 decimal places. Round your answers to the nearest whole dollar.) Answer is complete but not entirely correct Complete this question by entering your answers in the tabs below. Units of Production Straight Line DDB Compute depreciation for each year (and total depreciation of all years combined) for the machine under each Units of production. Units of Production Depreciation per unit Depreciable Units Depreciation Expense Year 1 122,100 0.40 48,840 2 123,500 0.40 49,400 3 120,600 0.40 48,240 124,800 4 0.40 49,920 Answer is complete but not entirely correct. Complete this question by entering your answers in the tabs below. Units of Production Straight Line DDB Compute depreciation for each year (and total depreciation of all years combined) for the machine under each Double- declining-balance. DDB Depreciation for the Period End of Period Beginning of Period Book Value Depreciation Expense Accumulated Depreciation Depreciation Rate Book Value Year $ 210,400 $ 105,200 105,200 1 50 $ 105,200 2 105,200 50 52,600 157,800 52,600 26,300 184,100 3 52,600 50 % 26,300 4. 26,300 50 8,300 192,400 18,000 192,400 Units of Production DDB 96