Refer to the following information: Researchers conducted a study to evaluate which of two medications, Drug A or Drug B, is more effective in treating headaches. Each patient was administered Drug A for one headache and Drug B for a different headache. The amount of time to pain relief was recorded in the table below. The sample standard deviation of the differences between the relief time of Drug A and the relief time of Drug B is 2.1213. Using a 0.05 significance level, you need to test the claim that the relief time for Drug A is different than the relief time for drug B. To do so, answer each of the following questions. Drug A Relief Time 20 40 45 19 27 32 26 Drug B Relief Time 18 30 46 15 22 29 25 Q7 What is the most appropriate statistical test for the given claim? Select one: a. Two-sample z-test O b. Wilcoxon rank-sum test O c. Two-sample (pooled variance) t-test O d. Two-sample (unpooled variance) t-test O e. Paired t-test Q 8 What is the null hypothesis Ho? Select one: O a. Hd = 0 O b. Hd * 0 O C. H1 - H2 = 0 O d. H 1 - H2 * 0 O e. X1 - X2 = 0 Of. x1 - X2 * 0