Explain how new uses of energy transformed native american

1.why does the term “energy” feature so prominently in West’s Contested Plains? Explain how new uses of energy transformed Native American lives on the plains in the eighteenth century, and then led to their undoing in the 1860s.
2. Identify several ways in which mining shaped the history of Colorado from 1859-1900. Why did mining assume less importance in the state after 1900?