Suppose we randomly sample 3 items from Home Depot and obtain the following prices: $47, $52, $73. Then we visit Lowe's and obtain the prices of the exact same products as: $49, $51, $77. What is the margin of error of a 90% confidence interval for the population mean difference in prices at Home Depot versus Lowe's. 6.3 4.24 2.39 36.8 We obtain a random sample of four 6-cylinder cars and record gas mileage of 21, 23, 19, 29. In an separate random sample of 8-cylinder cars, we record gas mileage of 27, 18, 29, 22. What is the lower bound of the 85% confidence interval for the difference in mean gas mileage between 6-cylinder cars and 8-cylinder cars, where difference is defined as 6-cylinder minus 8-cylinder. -7.3 -1 -6.3 -5.7 Suppose a test is given to 20 randomly selected college freshmen in Ohio. The sample average score on the test is 12 points and the sample standard deviation is 4 points. Suppose the same test is given to 16 randomly selected college freshmen in lowa. The sample average score on the test is 8 points and the sample standard deviation is 3 points. We want to test whether there is a significant difference in scores of college freshmen in Ohio versus lowa. What is the point estimate for the difference in population means, where difference is defined as (Ohio minus lowa)? 3.43 0 0 O not enough information