The correct answer is experiment
Experiment is <em>"a type of scientific research in which the researcher manipulates and controls one or more independent variables and observes the variation in dependent variables concurrently with the manipulation of independent variables."
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The purpose of manipulating and measuring the variables in the experiment is to capture causality (relationship between cause and effect). Independent variables are responsible for possible causes, and dependent variables signal the effects. Two variables may have a very high correlation, but not necessarily one cause the other. There are three conditions for admitting causality
Hi there!
One such reason is the fact that the UN's job is to maintain peace and help other countries. If the president went to them, he can see what they think the best option is, being as they are not just apart of the US, and their main objective is to help other countries!
Hope this helps!