Answer:
He was responsible for Portugal's influence in the Great Age of Exploration. Because of him Portuguese explorers were the first to sail to Africa's Gambian river.
It is false that Communism was the dominant economic force of the twentieth century, although it certainly overtook a great deal of territory. Capitalism was still overall dominant.
I think it was the decimal system and concept of zero
The United States of America joined World War II when Pearl Harbor was bombed...if you're referring to the 2nd World War.
