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The U.S. Energy Information Administration (US EIA) reported that the average price for a gallon of regular gasoline is $3.96. The US EIA updates its estimates of average gas prices on a weekly basis. Assume the standard deviation is $.24 for the price of a gallon of regular gasoline and recommend the appropriate sample size for the US EIA to use if they wish to report each of the following margins of error at 95% confidence. Round up to the next whole number. a. The desired margin of error is $.09. The appropriate sample size is b. The desired margin of error is $.07. The appropriate sample size is c. The desired margin of error is $.05. The appropriate sample size is