This period is called "The Great Wave of Immigration because?

Periods that experienced large and enduring increases in immigration to the western part of the United States of America

Explanation:

theodore roosevelt challenged william to a duel, whoever won, got their policy sent to congress. it ended up in a stalemate, and both men were injured and sent to the hospital.

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.