9.2. Let (X0, X1, ..., Xn) be an adapted stochastic process in the N-period binomial model. Define a random variable T:N + {0, 1, ..., N, 00} by T(W) = min{n : Xn >0}. Show that t is a stopping time. 9.2. Let (X0, X1, ..., Xn) be an adapted stochastic process in the N-period binomial model. Define a random variable T:N + {0, 1, ..., N, 00} by T(W) = min{n : Xn >0}. Show that t is a stopping time