What was an effect of the transatlantic slave trade on africa between 1500 and 1800?

24-karat gold is considered to be pure gold. 18-karat gold is considered to be about 75% gold. what is 18-karat gold considered a mixture rather than a pure substance? a) it has a variable composition of other elements and minerals. b) its color is different than pure gold. c) the gold atoms are not arranged in a repeating pattern. d) it can be melted and transformed into a different substance.

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Give an example of a situation in which an individual's pursuit of economic self-interest may not benefit but instead harm the rest of society