Final answer:
Advertisements for slave sales in colonial American newspapers attest to the widespread practice of slavery, signify the open exchange of human beings as property, and reflect the societal acceptance of racial inequality and white supremacy.
Step-by-step explanation:
The existence of newspaper advertisements such as the 'Sale of Slaves in Charleston, South Carolina' provides a clear record of the practice of slavery in colonial America. This indicates that the slave trade was an openly conducted business at the time, wherein human beings were bought and sold as property. These advertisements not only serve as primary sources of documentation but also reflect the underlying societal values and attitudes towards African-Americans, manifesting racial inequality and the accepted culture of white supremacy during that period in history.
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