The completion of separate depreciation schedules for each of the alternative depreciation methods is as follows:
<h3>a. Straight-line Method:</h3>
Year          Cost         Annual Depreciation     Accumulated      Net Book 
                                                                          Depreciation          Value
Year 1     $20,000             $4,455                       $4,455            $15,545
Year 2    $20,000             $4,455                          8,910              11,090
Year 3    $20,000             $4,455                        13,365              6,535
Year 4    $20,000            $4,455                        17,820               2,180
<h3>b. Units-of-production Method:</h3>
Year          Cost         Annual Depreciation     Accumulated      Net Book 
                                                                          Depreciation          Value
Year 1     $20,000             $7,128                         $7,128            $12,872
Year 2    $20,000            $5,346                         12,474               7,526
Year 3    $20,000            $3,564                        16,038               3,962
Year 4    $20,000            $1,782                         17,820               2,180
<h3>c. Double-declining-balance Method:</h3>
Year          Cost         Annual Depreciation     Accumulated      Net Book 
                                                                          Depreciation          Value
Year 1     $20,000             $10,000                       $10,000         $10,000
Year 2    $20,000              $5,000                          15,000            5,000
Year 3    $20,000             $2,500                           17,500            2,500
Year 4    $20,000                $320                           17,820             2,180
<h3>Data and Calculations:</h3>
Cost of asset = $20,000
Residual value = $2,180
Depreciable amount = $17,820 ($20,000 - $2,180)
Estimated productive life = 4 years or 9,900 hours
<h3>Annual depreciation rates:</h3>
Straight-line method = $4,455 ($17,820/4)
Units-of-production Method per unit = $1.8 ($17,820/9,900)
Double-declining-balance Method rate = 50% (100/4 x 2)
Learn more about depreciation methods at brainly.com/question/25806993
#SPJ1