A professor is looking to buy a new car. She would like to know if Domestic cars have longer life than Import cars. She collected the following sample data, along with population standard deviation, to test her hypothesis:

	Domestic	Import
Sample mean	19years	16.5years
Sample size	12	15
Population standard deviation	9years	8years

Use the p-value value approach to test this hypothesis with = 0.05. a) Determine the point estimate for the difference between population means. b)Calculate a 95% confidence interval for the difference between population means. c) Perform a test of the hypothesis that the mean for Domestic cars is higher than that for the Import cars, at a 95% confidence level. Show all parts of the hypothesis test, including your hypothesis, your test-statistic calculation, your p-value calculation, and your conclusion.