1?. 18. 19. 20. The EPA rates the mean highway gas mileage of the 2020 Hyundai Elantra GT to be 28 miles per gallon. Assume the standard deviation is 3 miles per gallon. A rental car company buys 50 of these cars. What is the probability that the mean mileage of the eet is less than 27 miles per gallon? (a) 0.9909 (c) 0.5000 (e) 0.009 (b) 0.164? ((1) 0.0369 The heights of a pediatrician's 200 three-year-old females are normally distributed with mean 37.82 inches and standard deviation 3.52 inches. Find the height of a three-yearold female at the 85''1 percentile. That is, nd the height for a three-yearold female that separates the bottom 85% from the top 25%. (a) 38.09 inches (c) 37.92 inches (e) 75 inches (b) 41.4? inches (d) 40.91 inches To assess the accuracy of a laboratory scale, a standard weight that is known to weigh 1 gram is repeatedly weighed a total of n times and the mean x of the weighing's is computed. Suppose the scale readings are normally distributed with unknown mean ,u and standard deviation 0' = 0.056 g. How large should it be so that a 95% condence interval for ,u has a margin of error of 10.01? 3:) 13 (:1) 340 (e) 1630 ) 163 ( ) 121 To test H0 : 1.1 d = 0 versus H A : t a, at 0 at a = 0.01, a random sample of size n=25 is obtained from a population that is known to be normally distributed. If the mean difference is determined to be c? = 5.25 and the sample standard deviation of the difference is S\