An article in the ACI Materials Journal (Vol. 84, 1987, pp. 213-216) describes several experiments investigating the rodding of concreteto remove trapped air. A 3-inch x 6-inch cylinder was used, and the number of times this rod was used is the design variable. Theresulting compressive strength of the concrete specimen is the response. The data are shown in the following table.Compressive Strength (psi)Rodding LevelObservations10153015301440151610165015002015601730153025150014901510(a) Is there any difference in compressive strength due to the rodding level? Use a = 0.05.Calculate to 2 decimal places fo:Is there statistical evidence to say that rodding level affects compressive strength?(b) Find to 2 decimal places the P-value for the F-statistic computed in part (a).P-value = i(c) Analyze the following residual plots to determine model adequacy.Does the assumption of normality seem reasonable?Does there appear to be an outlier in the data?Does the assumption of constant variance seem reasonable?>> Nomai Protability Piat of the Residualsiree s STREMOTH)-100100ResiduelResda svarsusRODNG28RCDD NGRescualsversusthe Fitted Values" Akeacas EeN

Objective: To determine if there is any difference in compressive strength due to rodding level

An article in the ACI Materials Journal (Vol. 84, 1987, pp. 213-216) describes several expe to remove trapped air. A 3-inch x 6-inch cylinder was used, and the number of times this resulting compressive strength of the concrete specimen is the response. The data are sl Compressive Strength (psi) Rodding Level Observations 10 1530 1530 1440 15 1610 1650 1500 20 1560 1730 1530