A publisher wants to estimate the mean length of time (in minutes) all adults spend reading newspapers. To determine this estimate, the publisher takes a random sample of 15 people and obtains the results below. From past studies, the publisher assumes the standard deviation is 1.9 minutes and that the population of times in normally distributed. 10, 9, 11, 9, 7, 10, 11, 6, 12, 7, 6, 7, 10, 10, 8
The 90% confidence interval is?
The 95% confidence interval is? (round to one decimal place)