13. Assume that gas mileage for cars is normally distributed with a mean of 23.5 miles per gallon and a standard deviation of 10 miles per gallon. Show all work. Just the answer, without supporting work, will receive no credit. (a) What is the probability that a randomly selected car gets between 15 and 30 miles per gallon? (Round the answer to 4 decimal places) (b) Find the 75th percentile of the gas mileage distribution. (Round the answer to 2 decimal places)