There is increasing concern within the health sciences community over the use of electronic tobacco products. The article “Exposure to Tobacco and Nicotine Product Advertising: Associations with Perceived Prevalence of Use Among College Students” (Amer. J. College Health, Volume 66, 2018, Issue 8) reported on a study based on the Texas College Tobacco Project survey administered in 2016. In a sample of 5767 undergraduates ages 18–25, 9.1% said they had used electronic cigarettes at least once during the previous 30 days. Calculate and interpret a confidence interval using a 99% confidence level for the proportion of all students in the population sampled who used e-cigarettes during the previous 30 days.