AP US History question:

Explain why and how the role of the federal government changed as a result of the Civil War with respect to TWO of the following during the period 1861-1877: race relations, westward expansion, economic development.

The Civil War changed almost the entire landscape of race relations in the United States, since it abolished slavery, which was the basis of the South's economy. This also had implications for westward expansion since before the Civil War, new states could become slave states, wherein after the War they could not.