Lipitor is a drug used to control cholesterol. In clinical trials of Lipitor, 94 subjects were treated with Lipitor and 270 were given a placebo. Among those treated with Lipitor, 7 developed infections. Among those given a placebo, 27 developed infections. a. Use a 0.05 level of significance to test the claim that the rate of infection was lower for those treated with Lipitor. Use the critical value method. b. Construct the 95% confidence interval for the difference in the rate of infection for those taking Lipitor and those taking the placebo. c. Are the hypothesis test and the confidence interval giving the same result?