A computer costs$3500and its salvage value in 5 years is negligible

A computer costs$3500and its salvage value in 5 years is negligible. What is the book value after 351 years? If the machine is sold for$1500in Year5, how much gain or recaptured depreciation is there?
Assume
(a) Straight-line depreciation
(b) Double declining balance depreciation
(c)20% bonus depreciation with the balance using 5-year MACRS(d) MACRS depreciation
(e)There aretwo important considerations when disposing ofold computers-one environmental and
one personal. What are they, and how can you lessen the effect of each?