4. a) lConsider a large population with u = 60 and 0' = 10. Assuming nx'N E .05, nd the mean and standard deviation of the sample mean, :2, for a sample size of 18. b) Consider H0 : u = 55 versus Hl : u a: 55. Another random sample of 36 observations taken from the same population produced a sample mean of 52.6. Using a = .05, would you reject the null hypothesis? The population is known to be normally distributed with o = T