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Suppose that mean retail price per gallon of regular grade gasoline is $3.54 with a standard deviation of $0.10 and that the retal price per gallon has a bell-shaped distribution. NOTE: Please use empincal nule approximations for this problem. a. What percentage of regular prade gasoline selis for between $3.44 and $3.64 per gallon (to 1 decimal)? % \% c. What percentage of regular grade gasoline sells for more than $3.64 per gallon (to 1 decimal)