Researchers wanted to evaluate whether a certain herb improved memory in elderly adults as measured by objective tests. To do this, they recruited 90 men and 127 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. What type of experimental design is this?What is the population being designed? What is the response variable in this study?What is the factor? What are the treatments? Which of the following is correct?

Apopulation is a group of individuals of a single species existing together in an area. a population’s range, the area it occupies, changes over time. populations, in turn, may form a network, or metapopulation, connected by individuals that move from one group to another. within a population, the distribution of individuals can be random, uniform, or clumped, and the distribution is determined in part by the availability of resources. how might the geographic range of a species change if populations could not exchange individuals with each other? how would your answer depend on what type of metapopulation existed?

Congress checks on the power of the presidency by overriding a presidential reversal or veto. debating the bill in both of the houses. making laws without presidential review. sending the bill back to several committees

Abill in the texas legislature that would allow a county to establish a new community college would be classified as a