A random sample of the price of gasoline from 40 gas stations in a region gives the statistics below. Complete parts a) and b).
ybar = $3.79, s = $0.27
a) Find a 95% confidence interval for the mean price of regular gasoline in that region. ( __, __ ) (Round to three decimal places as needed.)
b) If we had the same statistics from a sample of 80 stations, what would the 95% confidence interval be now?(__, __) (Round to three decimal places as needed.)