a. Suppose YI,Y2,...,Y5 are independent normal random variables with mean, 6 and variance, :93 > 0 . Name the distribution and its parameters of: (2 marks) (2 marks) $qu _ 9) v02 iii. Determine the constant k such that the random variable U: will have a t- distribution (4 marks) iv. U 2 (3 marks) b. Let Y1, Y2 ..... Yn be a random sample from a normal distribution where the mean is 2 and the variance is 4. How large must n be in order that P(1.9 s 17 52.1)2039 (9 marks)