Researchers must utilize a control group in a scientific study because <span>it is important to show that between two groups that were similar from the beginning of the study, the one that received the manipulation is the one that changes. Note that the control group is the group in the experiment that does not receive manipulation by the experimenter and is thus used as basis for how the other test subjects changed. </span>
The first sentence is referring to a secondary reinforce while
the second sentence is referring to primary reinforce. A primary reinforce are
usually base on biological things such as the water we drink or food that we
eat while the secondary reinforce is base on the conditions that humans is
reinforcing such as money or grades.
Answer: When Congress was voting whether to declare war, some people voted yes and some voted no.
Explanation:
Notre Dame because it is considered to be Paris exact center