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:
The space invaders is the answer
Sophia was built under Justinian the first and he ordered many roman style corinthian columns and greek style hellenistic columns imported from Lebanon to support the structure.