1. Answer the following questions using the expansion path illustrated below. The price of labor is $4 per unit. K 10 2,000 units Units of capital 1,000 units Expansion path S R 0 10 20 30 40 50 60 70 80 90 100 Units of labor a. The price of capital is $ b. In the long run, 1,000 units of output is produced at the lowest possible total cost by employing units of labor. C. The marginal rate of technical substitution at point S is d. When producing 2,000 units in the long run, the marginal product of the 60"h unit of labor (MPL) is 5. The marginal product of capital (MPk) must equal