or a certain product, cost C and revenue R are given as follows, where x is the number of units sold in hundreds Cost C-X + 110vx +51 Revenue: 896(x - 4) + 30R =18,750 a. Find the marginal cost at x = 4. dx The marginal cost is estimated to be $ (Do not round until the final answer. Then round to the nearest hundredth as needed.) dR b. Find the marginal revenue dx at x = 4. The marginal revenue is estimated to be $ (Do not round until the final answer. Then round to the nearest hundredth as needed )