2. Rubber can be added to asphalt to reduce road noise when the material is used...
2. Rubber can be added to asphalt to reduce road noise when the material is used as pavements. Table shows the stabilized viscosity in cP of 15 specimens of asphalt paving material. To be suitable for the intended pavement application, the mean stabilized viscosity should be controlled. (a) establish 95% confidence interval for the mean value. (b) establish 95% confidence interval for the variance. specimen Stabilized viscosity 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 3193 3124 3153 3145 3093 3466 3355 2979 3182 3227 3256 3332 3204 3282 3170