It warned Roosevelt that Germany was developing an atomic bomb and encouraged him to start a nuclear program in the US that later became the Manhattan Project
Answer:
Slaves provided much of the labor on plantations that grew cash crops.
Plantations were the main economic activity in the American South during the antebellum period. These plantations cultivated cotton, tobacco, sugar, indigo, and rice. The warm climate, plentiful rainfall and fertile soil meant that the plantations were able to flourish. However, they were labour-intensive, and most workers were African slaves. Planters held dozens, or sometimes hundreds, of slaves, making slave labor very important to the economy of the Southern colonies.
