Which research method uses information that governments, businesses, and educational institutions have already made available for public use? a. survey b. correlational research c. cross-cultural research d. secondary analysis

The answer is; B

In this type of research, the researcher compared between variables from the different spheres and find a correlation.  There is no extraneous variable in this type of research. An example, in this case, would be finding a statistical relationship between funding, by the government, towards education in several financial years and the number of enrolled students in public universities.

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.