Answer:
D. federal system of government that divides powers between the states and the national government
Explanation:
The Constitution created a <u>federal system of government that divides powers between the states and the national government</u>.
<span>c running the army is the correct answer</span>
First, they made settlement of the West possible after the Civil War by connecting farmers (and miners, ranchers, loggers, and others) to markets.
Second, railroads helped to integrate different regions of the country economically.
They walked instead of riding the bus
