How did some people struggle to survive hard times?

What was the most important consequence of the large-scale ecological changes in africa two hundred thousand years ago?

Jane determines x = 4 and y = 1 is the solution to the following system of equations.

The first human skeleton found in oklahoma is estimated to be 9,000 years old. based on this age, which dates the skeleton to about 7,000 bce, the skeleton is most likely from the