8. Four random numbers, 1.165, 0.626, 0.075, 0.351, were generated by a computer code of a normal distribution with mean and variance o. Five more normal random numbers, 0.3035, 2.696, 1.059, 2.797, 1.2643, were generated by using the same variance o but a different mean 2. The record about the values of M1, M2, 0 was lost. Please use all available data to find (a) a 90% confidence interval of - M (b) A 95% confidence interval of o (c) A 90% confidence interval of