C. both a and b! :)
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In The Americas , Most African Slaves Were Sold To Work ___.
- On Plantations
Answer:
Groups use varied methods to try to achieve their aims including lobbying, media campaigns, publicity stunts, polls, research, and policy briefings.
The answer to this question is Bias
When researchers are being biased in their analysis, all of their analysis become really unreliable because it does not fully reflect to the truth.
To make the result of the researchers fully reliable, researchers need to base their analysis solely to the data at hand
The answer is the song dynasty 1000-1450 CE