concrete? cures, it gains strength. The following data represent the? 7-day and? 28-day strength in pounds...

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concrete? cures, it gains strength. The following data representthe? 7-day and? 28-day strength in pounds per square inch? (psi) ofa certain type of concrete. Complete parts? (a) through? (f) below.?7-Day Strength? (psi), x 2480 3330 2620 3380 3390 ?28-DayStrength? (psi), y 4120 4850 4190 5020 5220 ?(a) Treating the?7-day strength as the explanatory? variable, x, use technology todetermine the estimates of beta 0 and beta 1. beta 0almost equalsb0equals nothing ?(Round to one decimal place as? needed.) beta1almost equalsb 1equals nothing ?(Round to four decimal places as?needed.) ?28-Day Strength? (psi), y ?(a) Treating the? 7-daystrength as the explanatory? variable, x, use technology todetermine the estimates of beta 0 and beta 1. beta 0almost equalsb0equals Round to one decimal place as? needed.) beta 1almostequalsb 1equals Round to four decimal places as? needed.) ?(b)Compute the standard error of the? estimate, s Subscript e. sSubscript eequals ?(Round to one decimal place as? needed.) ?(c) Anormal probability plot suggests that the residuals are normallydistributed. Determine s Subscript b 1. Use the answer from part?(b). s Subscript b 1equals 0.1212?? ?(Round to four decimal placesas? needed.) ?(d) A normal probability plot suggests that theresiduals are normally distributed. Test whether a linear relationexists between? 7-day strength and? 28-day strength at thealphaequals0.05 level of significance. State the null andalternative hypotheses. Choose the correct answer below. A. Upper H0?: beta 1equals0 Upper H 1?: beta 1not equals0 Your answer iscorrect.B. Upper H 0?: beta 0equals0 Upper H 1?: beta 0not equals0C. Upper H 0?: beta 0equals0 Upper H 1?: beta 0greater than0 D.Upper H 0?: beta 1equals0 Upper H 1?: beta 1greater than0 Determinethe? P-value of this hypothesis test. ?P-valueequals Round to threedecimal places as? needed.) What is the conclusion that can be?drawn? A. Do not reject Upper H 0 and conclude that a linearrelation does not exist between the? 7-day and? 28-day strength ofa certain type of concrete at the alphaequals0.05 level ofsignificance. B. Reject Upper H 0 and conclude that a linearrelation does not exist between the? 7-day and? 28-day strength ofa certain type of concrete at the alphaequals0.05 level ofsignificance. C. Do not reject Upper H 0 and conclude that a linearrelation exists between the? 7-day and? 28-day strength of acertain type of concrete at the alphaequals0.05 level ofsignificance. D. Reject Upper H 0 and conclude that a linearrelation exists between the? 7-day and? 28-day strength of acertain type of concrete at the alphaequals0.05 level ofsignificance. Your answer is correct. ?(e) Construct a? 95%confidence interval about the slope of the true? least-squaresregression line. Lower? bound: ?(Round to three decimal places as?needed.) Upper? bound: ?(Round to three decimal places as? needed.)?(f) What is the estimated mean? 28-day strength of this concreteif the? 7-day strength is 3000? psi? A good estimate of the mean?28-day strength is 4740.81 psi. ?(Round to two decimal places as?needed.)

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a Given that 7day strength as the explanatoryindependent variable x and 28day strength as the predictivedependent variable y Then linear regression model isy b0 b1x eUsing the ordinary least square method we estimate thecoefficient b0 and b1We do the analysis in excel get the outputSUMMARY OUTPUTRegression    See Answer
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