please solve it .

Q5. A) Consider a sample X I, X 2,---, X n of normally distributed random variables with variance 0-2 = 11. Suppose that n = 21. (i) What is the value of c for which P(S" 2 c) 20.70? (ii) What is the value of c for which P(S2 s c) = 0.70? B) Consider a sample X l, X 2,- - -, X" of normally distributed random variables with mean 1.1. Suppose that n = 11. (i) What is the value of c for which P(| (if Ja)! SE 2 c) = 0.20? (ii) What is the value of c for which P(| (X p) f S | s c) =0.86