Suppose the Wt;, i = 1,2 are two Wiener cesses. Use Ito's Lemma in obtaining appro- priate stochastic differential equations for the following transformations. pro- (a) X; = (Wt,)4 (b) X, (W, + w,)? (Wh + Wt,)2 (c) X = t + e Wiz (d) X = e+Wiz