Final answer:
Olaudah Equiano worked as a slave in North America and the Caribbean before gaining freedom and advocating for abolition.
Step-by-step explanation:
The two places in the Americas where Olaudah Equiano worked as a slave were d) North America and the Caribbean. Equiano was originally from what is now Nigeria and was kidnapped and sold into slavery during the eighteenth century. His enslavement in the Caribbean and the southern British mainland colonies—what would become the United States—is a historical fact. After obtaining his freedom, Equiano settled in London and wrote a detailed account of his life, which serves as an important historical document revealing the horrors of the slave trade and the life of slaves in the Americas.