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 2.2 minutes and that the population of times is normally distributed.

Results: 9 11 8 9 7 11 12 6 10 10 10 6 12 8 12

Construct the 90% and 99% confidence intervals for the population mean.

A. The 90% confidence level is ___ , ___ . (Round to 1 decimal place as needed)
B. The 99% confidence level is ___ , ___ (Round to 1 decimal place as needed)
C. Which interval is wider?