18.Supreme Court Chief Justice Roger B. Taney decided all of the following in the Dred Scott case except... Slaves are considered property, not people.

Slavery can never be abolished by the Federal government.

A slave can only be freed after serving 10 years as a slave sentence.

A slave has no rights in court.

In which research method does a researcher change the value of one variable to determine how the change affects another variable? a. experiment b. observational research c. survey d. case study

Awaiver of the requirement for documentation of informed consent may be granted when: the investigator has no convenient place to store signed consent forms separate from the research datathe only record linking the subject and the research is the consent document and the principal risk is a breach of confidentiality.potential subjects might find some of the research questions embarrassing, personal, or intrusivethe subjects are literate in their own language; however, they do not read, write, or speak english

In which type of economy are these decisions made by the producers , consumers, and the goverment?