3.18 An experiment was run to determine whether four spe- cic ring temperatures affect the density of a certain type of Prick. A completely randomized experiment led to the follow- mg data: Temperature Density 100 21.8 21.9 21.7 21.6 21.7 125 21.7 21.4 21.5 21.4 150 21.9 21.8 21.8 21.6 21.5 175 21.9 21.7 21.8 21.4 u-:u-' (a) Does the ring temperature affect the density of the bricks? Use a = 0.05. (b) Is it appropriate to compare the means using the Fisher LSD method (for example) in this experiment? {1:} Analyze the residuals from this experiment. Are the analysis of variance assumptions satised