Final answer:
During the Industrial Revolution, American textile mills, coal mines, and steel foundries employed children as young as 7.
Step-by-step explanation:
In the 19th century, American textile mills, coal mines, and steel foundries employed children as young as 7.
The Industrial Revolution led to the increased demand for labor, and families in need of income often sent their children to work. These children were commonly hired in textile mills and coal mines, where they were paid low wages and exposed to dangerous conditions.