The pacific railroad a. was something most territories did not want on their land. b. small, isolated communities stay isolated. c. opened up frontiers and changed economic life. d. did not threaten the native american way of life.

The correct answer is C. Opened up frontiers and changed economic life

Explanation:

The Pacific Railroad was the first railroad that connected the eastern territories in the U.S. with the Pacific coast, this road was constructed from 1863 to 1869 and covered around 3000 kilometers from Nebraska to San Francisco Bay. This road had a great impact in the American society during the 19th and 20th century because it changed the economy by making easier, cheaper and faster the transportation of products and people from one coast to the other. Also, the construction of this railroad implied a connection between some of the states of the North with some of the South after the Civil war, which meant this railroad did not only connected isolated territories but helped to open up the frontiers between them. Considering the previous ideas it can be concluded the Pacific Railroad "opened up frontiers and changed economic life".

hawaii was the final state

4 copper and gold, the california gold rush is why im pretty sure.