3. A firm's cost and revenue functions are given by C(x) = 6x and R(x) = 9x -0.01.x2 Cl(a)=6os and Rev = v=0.023 * Siven by a) What is the firm's fixed- and variable cost? FC = 0; VC(x) = 6x b) What is firm's profit when it sells 100 units? Substitute 100 into the revenue and cost functions and find the profit. c) Find the firm's profit maximizing output