Aresearch engineer for a tire manufacturer is investigating tire life for a new rubber compound and has built 16 tires and tested them to end-of-life in a road test. the sample mean and standard deviation are 60,139.7 and 3645.94 kilometers. find a 95% confidence interval on mean tire life. compute a 95% prediction interval on the life of the next tire of this type tested under conditions that are similar to those employed in the original test.