4, from July 28th 1914 to November 11th 1918
You had to own land you had to own land you had to own land
Answer:In 1947, Salk took a position at University of Pittsburgh, where he began conducting research on polio, also known as infantile paralysis. By 1951, Salk had determined that there were three distinct types of polio viruses and was able to develop a "killed virus" vaccine for the disease.
Explanation:
Yes they did it helped them a lot
Answer:
<em>B</em><em>.</em><em>j</em><em>o</em><em>h</em><em>n</em><em> </em><em>L</em><em>o</em><em>c</em><em>k</em><em>e</em><em> </em>
<em>I</em><em> </em><em>t</em><em>h</em><em>i</em><em>n</em><em>k</em><em> </em><em>i</em><em>t</em><em>s</em><em> </em><em>h</em><em>e</em><em>l</em><em>p</em>
