What was the biggest cause for growth of railroads during the gilded age?

Transcontinental Railroads

Explanation:

Good needed to be transported.

 IT began during the Civil War, which spurred Congress and the northern states to build more railroads and increased demand for a variety of manufactured goods.

Explanation:

so what is your question?

"a government in which power is divided between state and national levels". federalism is a system of government in which entities such and state and province, share power with the national government.