Why is East Africa often called the "cradle of humanity"?

South america is located within which hemisphere?

What is a small water source like a stream or brook?

Which statement explains what upwelling causes? a. upwelling causes tides to rise and fall. b. upwelling causes changes in the direction of currents. c. upwelling causes nutrients, minerals, and tiny organisms to rise. d. upwelling causes currents in the pacific ocean to change direction. i think the answer is c.