f) Is the vaccine effective in lowering ear infection? 7) To test if Vitamin C is effective in lowering the rate of catching common colds, subjects in treatment group were treated with a daily dose of vitamin C while the control group took a placebo. 35 of 42 subjects in the treatment group develop the cold in winter. In the control group, 92 of 108 subjects develop the cold. Use a significant level of 0.01 to test the claim. a) Define populations and identify the test parameters. b) Use confidence interval to test the claim. What appropriate C-level should be used? What is the confidence interval of difference in percent of people who take vitamin C and not taking vitamin C. c) Use the confidence interval to write the conclusion about the claim. d) Based on the above result, is vitamin C effective in lowering the percentage of people catching common cold