The demand function p = D(x) = -0.2x + 39 and the total cost function C(x) = 1.3x + 8.4x + 65 for a particular commodity are given in terms of the level of production x. a. Find the revenue R(x) and profit P(x). b. Find all values of x for which production of the commodity is profitable. Oa. R(x) = -0.2x + 39x; P(x) = -1.5x + 30.6x-65 b. 2.41 < x < 17.99 O a. R(x) = -0.2x + 39; P(x) = -1.5x2 + 30.6x-65 b. x 2.41 Oa. R(x) = -0.2x + 39x; P(x) = 1.5x2 - 30.6x + 65 b. x 2.41 Oa. R(x) = -0.2x + 39; P(x) = 1.5x - 30.6x + 65 b. 2.41 < x < 17.99