How did the Civil War affect the Northern and Southern economies?

The Civil War benefited the Northern economy, but it left the Southern economy in absolutely terrible condition. The South, with its agricultural economy, lost its ability to exploit slave labor for greater profits, and also, most battles occurred in Southern territory, leaving huge spans of agricultural land destroyed. The North had a more industrialized economy and therefore benefited from the railroad boom and the manufacturing of wartime products.

a and b!

dfroos means which is a and b