Fuel economy again The combined gas mileage of midsize cars varies with mean 24 miles per gallon (mpg) and a standard deviation of about 5.5 mpg. A particular rental car agency typically has 150...

Fuel economy again The combined gas mileage of midsize cars varies with mean 24 miles per gallon (mpg) and a standard deviation of about 5.5 mpg. A particular rental car agency typically has 150 midsize cars in its lot. Let y represent the mean combined gas mileage for all cars in the lot.

 a) What’s the approximate model for the distribution of y? Explain.

 b) Estimate the probability that y is between 25 and 27 mpg.

 c) There is only a 5% chance that the mean combined gas mileage is greater than what value?