[29] Let X1, X2, ..., X20 be a random sample from a N(0, 62) distribution. It is desired to construct a 95% confidence interval for 2 and to test Ho : 62 = 2 against H1 : 62 > 2 at the 0.05 level of significance. Note: The sample size is n = 20. 20 (a) Justify that the distribution of 2 = _ X 20 distribution? (3) 1= 1 (b) Find a and b (a b). (4) 20 (c) Use parts (a) and (b) to show that (0.0293 x?, 0.1043 ) X? is a 95% confidence Ex ? ) is a i=1 interval estimator for o2. Hint: What is P(a s Q s b)? (6) (d) Show that the uniformly most powerful test for Ho : 62 = 2 against H1 : 62 > 2, at the 20 0.05 level of significance, rejects Ho if Q => 2 31.41. Note: The sample size is 2