How did the first humans get to north america

Atown is built on the banks of a small lake on the edge of a desert. after some time, the townspeople discover that water from the lake has become too polluted to use. describe one way that the lake may have been contaminated by the actions of the townspeople, and explain how the townspeople can remediate this problem.

Which country in the video has the highest population growth rate?

How can studying economics us make better choices about how to use scare resources