How did the economies of the north and south differ

In the North, the economy was based on industry. They built factories and manufactured products to sell to other countries and to the southern states. They did not do a lot of farming because the soil was rocky and the colder climate made for a shorter growing season. ... In the South, the economy was based on agriculture.

the border between arizona and new mexico is a thin, black line; this indicates a state boundary.

its correct: it's a thin line, and it's a state boundary, correct