14. For the stock price process where dz is the Weiner process, is the expected rate of return on the stock and is the volatility of the stock price; suppose f is the price of a derivative that is contingent on S; the Black-Scholes-Merton differential equation governs all the derivatives that can be defined with S.

a)Show the Black-Scholes-Merton differential equation for f

1. What is the boundary condition of this equation for a European put option when .