Answer:
1. See file attached that shows three depreciation schedules.
2. The Units of Production tracks the wear and tear on the equipment most closely.
Explanation:
Schedule of depreciation expense, accumulated depreciation, and book value per year for the equipment under the three depreciation methods is attached.
Straight-line
Depreciation expense =6750=(Original Value -Residual Value)/Useful life
Units-of-production
Units of Production Rate=4=(Original Value -Residual Value)/estimated productive life
Double-declining-balance.
Depreciation rate  20,00% 1/useful life *100