The XYZ Block Company purchased a new office computer and other depreciable computer hardware for $4800. During the third year, the computer is declared obsolete and is donated to the local community college. Using an interest rate of 15%, calculate the PW of the depreciation deductions. Assume that no salvage value was initially declared and that the machine was expected to last 5 years.
(a) Straight-line depreciation
(b) Sum-of-the-years'-digits depreciation
(c) MACRS depreciation