A delivery truck costs $20,000 and has an estimated residual value of $2,000 at the end of its estimated useful life of five years. Assume the truck was used 20,000 miles during year 1; 30,000 miles during year 2; 10,000 miles during year year 3; 20,000 miles during year 4; and 10,000 miles during the fifth year.

Calculate Depreciation Expenses for each year using: (a) Straight- Line Method (b) Units of Production Method (c) Double-Declining-Balance Method