Answer:
American Civil War - War between the Union Army of the United States and the Confederate Army of the South.
Slavery - Taking away freedom and making people work with no rights.
Underground Railroad - Network of secret routes that allowed slaves to escape to the north .
Thomas Edison - Inventor of the phonograph.
Explanation:
D. The average 8 to 18-year-old spends <em><u>3 hours or more</u></em> per day on average in front of a screen doing very little to no physical activity.