<em>In the </em><em>late 19th century</em><em>, immigrants came to the United States in droves. The absolute number of immigrants in the country rose from less than </em><em>2.5 </em><em>million in </em><em>1850 </em><em>to more than </em><em>13.5 </em><em>million in </em><em>1910</em><em>. That boosted immigrants as a share of the population to </em><em>15%</em><em>, from </em><em>10%</em><em>, over the period.</em>
The main reason for the rapid settlement of the Great Plains was
<span>"(A) free land" although it should be noted that the land was not always free. It was always cheap, however. </span>
In both the 1920’s and 1950’s in America there was a economic boom from after the war.