A random sample of 49 measurements from one population had a sample mean of 10, with sample standard deviation 5. An independent random sample of 64 measurements from a second population had a sample mean of 13, with sample standard deviation 6. Test the claim that the population means are different. Use level of significance 0.01. LA USE SALT (a) What distribution does the sample test statistic follow? Explain. O The standard normal. We assume that both population distributions are approximately normal with unknown standard deviations. O The Student's t. We assume that both population distributions are approximately normal with unknown standard deviations. O The standard normal. We assume that both population distributions are approximately normal with known standard deviations. O The Student's t. We assume that both population distributions are approximately normal with known standard deviations. X b) State the hypotheses. O Ho: M1 = HziH1: H1 > H2 O HO: M1 # Hzi H1: M1 = H2 O Ho: M1 = 12; H1: H1 0.500 O 0.250