Which states separated as a result of disagreements regarding secession

American Civil War: secession

On April 12, 1861, Confederate guns opened fire on the fort, and the Civil War began. Forced now to make a choice between the Union and the Confederacy, the states of the Upper South—Virginia, North Carolina, Arkansas, and Tennessee—voted to secede.

Explanation:

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on this day in 1913, henry ford installs the first moving assembly line for the mass production of an entire automobile. his innovation reduced the time it took to build a car from more than 12 hours to two hours and 30 minutes.

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.