Question 6 The distribution of scores on a recent test closely followed a Normal Distribution with a mean Type numbers in the boxes. of 22 points and a standard deviation of 2 points. For this question, DO NOT apply the aby Part 1: 5 points standard deviation rule. aby Part 2:5 points 10 points (a) What proportion of the students scored at least 26 points on this test, rounded to five decimal places? (b) What is the 20 percentile of the distribution of test scores, rounded to three decimal places? Question 7 The Environmental Protection agency requires that the exhaust of each model of motor vehicle Type numbers in the boxes. be tested for the level of several pollutants. The level of oxides of nitrogen (NOX) in the exhaust aby Part 1: 5 points of one light truck model was found to vary among individually trucks according to a Normal aby Part 2: 5 points distribution with mean 1.45 grams per mile driven and standard deviation 0.40 grams per mile. 10 points (a) What is the 60th percentile for NOX exhaust, rounded to four decimal places? (b) Find the interquartile range for the distribution of NOX levels in the exhaust of trucks rounded to four decimal places