1) Let X1, X2, ..., Xn be independent and identically distributed standard normal random variables. Your answers for the following can include n. a) What is the distribution of Y = En, Xi^2? b ) For Y as defined in part c), find an approximation for P(Y> 2n) using the Central Limit Theorem. Express your final answer using the CDF of a standard normal random variable. (Hint: consider the distribution of Y, which is the average of X12, .. ., Xn2. )