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54q The cost function for q units of a certain item is C(g) = 90g + 106. The revenue function for the same item is R(q) = 90q + Find the marginal cost. b. Find the profit function. c. Find the profit from one more unit sold when 8 units are sold. a. The marginal cost is b. P(g) = c. The profit from one more unit when 8 units are sold is approximately $ (Type an integer or decimal rounded to two decimal places as needed.)