You are given the following data: Group 1 1,1+,2,2+,2+,3 Group 2 1,2+,2+,2,3+,4 Group 3 1+,2,2,2+,3,3+,4+ +: right censored A cox regression model is used for modeling the data. The maximum (partial) likelihood estimator of hazard ratios from Groups 2 and 3 compared with Group 1 are 0.6247 and 0.5107, respectively, when Breslow's approximation is used. Test the hypothesis that there are no difference among groups using 5% level of significance using [15 marks each] (a) Wald test (b) Score test (c) Likelihood ratio test [15 marks] Refer to last question, construct a 95% confidence interval for the hazard ratio from Group 2 compared with Group 3