Question No. 8-11: A random sample was selected from a population having a normal distribution. Calculate a 90% confidence interval estimate for μ for each of the following situations: a. ∑x = 134, n...

Question No. 8-11:

A random sample was selected from a population having a normal distribution. Calculate a 90% confidence interval estimate for μ for each of the following situations:

a. ∑x = 134, n = 10, s = 3.1

b. ∑x = 3,744, n = 120, s = 8.2

c. ∑x = 40.5, n = 9, σ = 2.9

d. ∑x = 585.9, ∑x²= 15,472.37, n = 27