4. Use the following information to compute values for each the following items. (20 points) Net farm income $ 36,000 $220,000 $360,000 S 11,000 $109,000 Opportunity cost of labor Opportunity cost of management Family living expenses Income and social security taxes Opportunity cost of capital $16,000 $ 8,000 $20,000 $ 4,000 10% Average equity verage asset value Interest expense Gross revenue a. Rate of return on assets b. Rate of return on equity c. Operating profit margin ratio d. Change in equity $ c. Return to management S % % -- S. Depreciation. Matt Brown, a farmer, just purchased a new farm tractor for $80,000. At the end of expected economic life (7 years) of this tractor, it will have a salvage value of 10 percent of its original purchased price. Use four (4) methods of depreciation discussed in class to calculate depreciation for each of the years of economic life. Show all formulas, calculations and results below