Answer:
Conflict, insecurity, weak institutions and limited access to justice remain a great threat to sustainable development.
<u>Positive Economists'</u> purpose is to create an explanation of a certain economic phenomena.
These economists use statistics in order to find out the aggregate behavior of the people because of a certain economic decisions. From this, they can developed an understanding to explain the economic phenomena.
<u>The normative economists' </u>purpose is to find out whether a certain economic decision achieve its original purpose.
They used statistic as a quantitative measurements. They determine the goals of a certain economic policy and They compared the statistic before the economic policy was implemented to the condition after the implementation .
This will help them know whether the policy achieve its original goals.
For example. if a certain policy was created to reduce unemployment, normative economists will compare the data/statistic about the number of employment before and after the policy.
Native Americans, establishing trade, society, and agriculture
We (as in 2016) cannot use the land bridge because of the melting of the glaciers. Back then the glaciers were still in one piece and the sea levels were much lower than now. This allowed the early people to cross the bearing straight.
Because they found out that Copernicus was right all along.