5)The Environmental Protection agency requires that the exhaustof each model of motor vehicle be tested for the level of severalpollutants. The level of oxides of nitrogen (NOX) in the exhaust ofone light truck model was found to vary among individually trucksaccording to a Normal distribution with mean 1.45 grams per miledriven and standard deviation 0.40 grams per mile. (a) What is the20th percentile for NOX exhaust, rounded to four decimal places?(b) Find the interquartile range for the distribution of NOX levelsin the exhaust of trucks rounded to four decimal places.
