This graph shows a large number of immigrants to the United States in the early 1900s. Why was there a sharp increase in immigra
nts during this time? shows a graph
a. transition from steam ships to airplanes
b. rapid development of technology
c. reduction of the railroads in favor of other transportation
Explanation: When a geologist studies 3 rock layers (and their fossils) there is the good chance that the upper layer is the youngest and the lowest layer is the oldest