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Question 1 1 pts A researcher is interested in testing the popular belief that herbal remedies like Ginko Biloba and Ginseng may improve learning and memory. She obtains a sample of 16 participants. She has each person take the herbal supplements every day for 90 days. At the end of the 90 days, each person takes a standardized memory test. For the general population, scores from the memory test form a normal distribution and they have a mean of 50 and a standard deviation of 12. The sample of the 16 research participants had an average memory score of 54. Assuming a two-tailed test, what would the null hypothesis be? IA The herbal supplements Ginko Biloba and Ginseng will improve memory A The herbal supplements Ginko Biloba and Ginseng will have an effect on memory A The herbal supplements Ginko Biloba and Ginseng will not have an effect on memory Question 2 1 pts A researcher is interested in testing the popular belief that herbal remedies like Ginko Biloba and Ginseng may improve learning and memory. She obtains a sample of 16 participants. She has each person take the herbal supplements every day for 90 days. At the end of the 90 days, each person takes a standardized memory test. For the general population, scores from the memory test form a normal distribution and they have a mean of 50 and a standard deviation of 12. The sample of the 16 research participants had an average memory score of 54. Using the standard S-step procedure, conduct a two-tailed hypothesis test with a=.05 to evaluate the effect of the supplements. What is the z-score that corresponds to the boundaries of the critical region