The bond behavior of reinforcing bars Is an Important determinant of strength and stability. The article "Experimental Study on the Bond Behavlor of Reinforcing Bars Embedded In Concrete Subjected to Lateral Pressure"? reported the results of one experiment in which varying levels of lateral pressure were applied to 21 concrete cube specimens, each with an embedded 16 mm plain steel round bar, and the corresponding bond capacity was determined. Due to differing concrete cube strengths \"cu! in MPa), the applied lateral pressure was equivalent to a xed proportion of the specimen's fcu (0, D'lfcu' . . @- Pressure | 0 0 0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 ., O'Efcu)' Also, since bond strength can be heavily inuenced by the specimen's 0.3 0.3 0.4 Ratio Pressure | 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 Ratio l0.355 0.239 0.365 0.319 0.312 0.394 0.385 0.320 (a) Does a scatterplot of the data support the use of the simple linear regression model? l0.123 0.100 0.101 0.172 0.133 0.107 0.217 0.172 0.151 0.263 0.227 0.252 0.310 [cm bond capacity was expressed as the ratio of bond strength (MPa) to O A scatterplot of the data shows a weak, negative, linear relationship between pressure and the bond capacity ratio and supports the use of a simple linear regression model. 0 A scatterplot of the data shows a reasonably strong, negative, linear relationship between pressure and the bond capacity ratio and supports the use ofa simple linear regression model. A scatterplot of the data shows a reasonably strong, positive, linear relationship between pressure and the bond capacity ratio and supports the use of a simple linear regression model. 0 A scatterplot of the data shows a reasonably strong, negative, linear relationship between pressure and the bond capacity ratio and does not support the use ofa simple linear regression model. 0 A soatterplot of the data shows a weak, positive, linear relationship between pressure and the bond capacity ratio and does not support the use of a simple linear regression model. (5) Use the accompanying Minitab output to give point estimates of the slope and intercept of the population regression line. (Enter your answers to ve decimal places.) Predictor Coef SE (1er 1' P Constant 0.10121 0.01308 7.74 0.000 Pressure 0.46071 0.03627 12.70 0.000 s = 0.0332397 R-Sq = 89.5% R-Sqiadj) = 88.9% Analysis of Variance Source DP SS KS 2' Regression 1 0.17830 0.17830 161.37 0.000 Residual Error 19 0.02099 0.00110 Total 20 0.19929 slope 0.454 x intercept 'Elx The regression equation is Ratio = 0.101 + 0.461 Pressure (c) Calculate a point estimate of the true average bond capacity when lateral pressure is 0.46fcu. (Round your answer to four decimal places.) _x (d) What is a point estimate of the error standard deviation 6? (Enter your answer to seven decimal places.) _x How would you interpret the point estimate of the error standard deviation :7? O This represents the typical difference between the lateral pressure applied to a bar and the ratio predicted by the least squares regression line. 0 This represents the typical difference between a concrete specimen's actual bond capacity ratio and the lateral pressure predicted by the least squares regression line. 0 This represents the ratio predicted by the least squares regression line for a value of 1. O This represents the typical difference between a concrete specimen's actual bond capacity ratio and the ratio predicted by the least squares regression line. 0 This represents the typical difference between the lateral pressure applied to a bar and the lateral pressure predicted by the least squares regression line. (e) What is the value of total variation? (Enter your answer to five decimal places.) :1 What percentage of it can be explained by the model relationship? (Enter your answer to one decimal place.) l:l%