2. (30 Points) Vital capacity is a measure of the amount of air that someone can exhale after taking a deep breath, Data was collected on brass players and a control group. Assume the population distributions were normal. Table 1: Table for Question 2 Brass Player Control Group 4.7 4.2 4.6 4.7 4.3 5.1 4.5 4.7 5.5 5.0 4.9 - 5.3 - (a) (10 Points) Conduct a t test to determine whether the population mean for brass is larger than that for control. (b) (5 Points) Provide the 95% confidence interval for the difference in the two population means. (c) (15 Points) A researcher claims that in theory the "spread/variance" in the two popu- lations is the same. Repeat step 1 (and 2) utilizing this assumption with the argument "var.equal" within the "t.test" function.

Fig: 1