posted by aaron need urgent help .
please help me I've waited for hours
The average price of a gallon of unleaded regular gasoline was reported to be $2.34 in northern Kentucky (The Cincinnati Enquirer, January 21, 2006). Use this price as the population mean, and assume the population standard deviation is $.20.
1) Calculate the sample size necessary to guarantee at least .95 probability that the sample mean is within $.03 of the population mean