Which historical event most caused the us urban population to climb from 6 million to 44 million between 1860 and 1910?

Will have the greatest effect on human health. pollution in the a. troposphere b. stratosphere mesosphere d. thermosphere

Compare and contrast the treatment of different religions by rulers of the arab empire as soon as you can with i've been working on this test for like an hour and a half and i'm super stressed : (

Plz . explain what shopping was like in london during the early 1900s. how does this differ from the modern shopping experience?