Final answer:
Industrial manufacturing was the economic activity growing rapidly in the North during the mid-1800s.
Step-by-step explanation:
During the mid-1800s, industrial manufacturing was growing rapidly in the North.
As the Industrial Revolution took place, the North experienced significant advancements in manufacturing and technology. Factories were established, producing goods such as textiles, machinery, and iron products. This led to the growth of cities and an increase in population as people moved from rural areas to urban centers to work in factories.
This economic activity in the North contrasted with the Southern economy, which primarily relied on plantation farming.
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