A consumer advocacy group is very concerned about the fluctuation of the price of gas in the Greater Rochester Area. On a daily basis, the group randomly selects 50 gas stations in the G.R.A. and records the price of regular grade gas.
Suppose today's sample yielded a mean of $4.19 and a standard deviation of $0.10, create and interpret a 99% confidence interval for the population standard deviation. Assume the distribution of gas prices in the area follows a normal distribution.