The Federalists promised to add: The Bill of Rights
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Answer:
vaccination
Explanation:
Louis Pasteur had been working to find a vaccine that would cure cholera in chickens. His lab assistant gave an older, weaker strain of the disease to the birds. When these birds did not die Pasteur began to rethink his ideas a came up with our current method of administering vaccinations.
Secondary Sources are useful because they offer a different point of view to past events. While most secondary sources are based on a primary source, they are still useful because of the analysis that they can offer compared to past stories.
