According to a recent survey, high school girls average 100

According to a recent survey, high school girls average 100 text messages daily (The Boston Globe, April 21, 2010). Assume that the survey was based on a random sample of 36 high school girls. The sample standard deviation is computed as 10 text messages daily.,a. Calculate the margin of error with 99% confidence.,b. What is the 99% confidence interval for the population mean texts that all high school girls send daily?