The correct answers:
1) tainted source is adulterated, biased and corrupted information that may eventually affect a study, trial, investigation.
2. Historical research is important because it can help students and teachers (masters, professors, educators) understanding with assurance the fact in a essay/ study/ investigation. The main purpose of historical research is preserving and interpreting facts correctly.
example of dubious secondary information: fake news, when there is divergent information about an official source of information. Often the source language is not appropriate, accurate, and unbiased.
George Washington, Benjamin Franklin, James Madison, Edmund Randolph, Alexander Hamilton, & <span>Governeur Morris.</span>
Answer: precedent
Explanation:
a previous case decision that may be or must be followed in similar cases.
The concept of nullification is a "legal theory that a state has the right to nullify, or invalidate, any federal law which that state has deemed unconstitutional with respect to the United States Constitution (as opposed to the state's own constitution)."