12) Designing a Study: (1 pts) Researchers wanted to evaluate whether a certain herb improved memory in elderly adults as measured by objective tests. To do this, they recruited 92 men and 125 women older than 70 years and in good health. Participants were randomly assigned to receive the herb, 45 mg 3 times a day, or a matching placebo. A measure of memory improvement was determined by a standardized test of learning and memory. Identify the experimental units. The placebo and 45 mg of the herb The 92 men and 125 women older than 70 who are in good health that participated in the study Elderly adults Men and women older than 70 who are in good health 13) Explain what statistical procedure should be used for the research objective (1pt5) given: Assuming all model requirements for conducting the appropriate procedure have been satised, is the mean IQ of the students in the professor's statistics class higher than that of the general population,100? Matched pairs t-test on the difference of two means Hypothesis test for a single mean Hypothesis test for two proportions with independent samples Condence interval for a single prOportion