Suppose you are told that a 95% confidence interval for the average price of a gallon of regular gasoline in...

Suppose you are told that a 95% confidence interval for the average price of a gallon of regular gasoline in your state is from $3.07 to $3.81. Use the fact that the confidence interval for the mean is in the form x − E to x + E to compute the sample mean and the maximal margin of error E. (Round your answers to two decimal places.)