how did the crusades encourage europeans to explore
The Crusades took thousands of men from Europe to Turkey, Israel, and other parts of the Middle East. There they learned of different ways of life and exotic products from many other parts of the world. Desire for these products encouraged explorers to find ways to distant lands.
what are the physical features of south africa?
Please check this site for the physical features of South Africa.
http://en.wikipedia.org/wiki/South_Africa#Geography
Where do many scholors think the first americans came from?