I solved (a), but I don't know how to solve (b) and (c), please help!!

(10 pts) In this problem you will use the MGF to prove that the square of the standard normal is a well known distribution. (a) (3 pts) Let Z ~ N(0, 1) (recall fz(z) = V/2T ez). Using the definition of MGF show that 1 Mzz (t) = e-4(1-21)2'dz -DO V2TT (b) (5 pts) Using your result from part (a) show that Mzz (t) = , for t