A numerically controlled milling machine was pur- chased for $95,000 four years ago. The estimated salvage value was $10,000 after 15 years. What is the machines book value now after 4 years of de- preciation? If the machine is sold for $20,000 early in year 5, how much of a gain on sale or recaptured depreciation is there? Assume:

(a) 7-year MACRS.

(b) Straight-line.

(c) Double-declining balance.

(d) SOYD.