$14$ Common stock value$-$All growth models You are evaluating the potential purchase of a small business currently generating $ $42,500$ of after$-$tax cash flow $($D$\_0=$$ $42,500).$ On the basis of a review of similar$-$risk investment opportunities, you must earn an $18\%$ rate of return on the proposed purchase. Because you are relatively uncertain about future cash flows, you decide to estimate the firm's value using several possible assumptions about the growth rate of cash flows. a$.$ What is the firm's value if cash flows are expected to grow at an annul rate of $0\%$ from now to infinity? b$.$ What is the firm's value if cash flows are expected to grow at a constant annual rate of $7\%$ from now to infinity? c$.$ What is the firm's value if cash flows are expected to grow at an annual rate of $12\%$ for the first $2$ years, followed by a constant annual rate of $7\%$ from year $3$ to infinity?