Suppose an engineer wanted to determine whether the gas mixture used increases gas mileage. He constructed a randomized block design and performed tests to measure the gas mileage. The data were determined to come from normally distributed populations and the variances were determined to be equal. Complete parts (a) through (e) below. Mix 1 Mix 2 Mix 3 D Car 1 27.8 27.9 28.7 Car 2 25.8 26.7 26.9 Car 3 25.9 25.9 25.? Car 4 25.9 25.9 27.4 Car 5 28.2 28.7 28.8 Car 6 24.9 24.9 25.7 (a) Normal probability plots for each treatment indicate that the requirement of normality is satised. Verify that the requirement of equal population variances for each treatment is satised. Since is less than twice . the requirement of equal population variances for each treatment (Round to two decimal places as needed.) is satisfied