how many rooms did the immigrants have to go through to be fully processed before leaving ellis island?

More than 12 million immigrants passed through Ellis Island between 1892 ... The process went something like this: Before the ship was allowed to ... “You could have as many as 1,500 passengers in third class alone. ... “Now, in 1907, no passports or visas were needed to enter the United States,” he says.

Explanation:

by 1880, germany had more rail lines than great britain and russia.