The Nile allowed civilizations in Nubia and Egypt to:
O
A. exchange goods and ideas.
O
B. build huge monuments to pharaohs.
O
O
C. conquer all of northern Africa.
D. avoid interacting with each other.

"if i have seen farther than others," said newton, "it is because i have stood on the shoulders of giants." who were the giants to whom newton was referring? could this be said of any scientific accomplishment? explain.