A market research analyst must estimate the average market share for a new product in the northeast region of the U.

A market research analyst must estimate the average market share for a new product in the northeast region of the U.S. She collected data for the last 36 quarters in a similar region for which the average market share was 16 percent with a sample standard deviation of 2.4 percent.

The standard t statistic for a 95% confidence interval is

The lower 95% confidence limit is

The width of the 95% confidence interval is