Using a computer-based list of registered students, 200 freshmen, 200 sopho- ors and 200 seniors were selected at random from each of these four 3. (5 points) u mores, 200 juni classes. what kind of sampling design was employed? 4. (15 points) researchers wanted to evaluate whether ginko, an over-the-counter herb marketed as enhancing memory, improves memory in elderly adults as measured by objective tests. to do this, they recruited 200 people older than 60 years of age and in good health. participants were randomly assigned to receive day, or a matching placebo. the measure of memory improvement after 6 weeks was determined by a standardized test of learning and memory (a) (2 points) what type of experimental design was this? ginko, 40mg 3 times per (b) (2 points) what is the population being studied? (c) (2 points) what is the response variable in this study? (d) (2 points) what is the factor? (e) (2 points) what are the treatments? (f) (5 points) draw a diagram experiment outlining the experiment (your diagram should have the same structure as the ones done in class or in the book).