Answer:
A
Explanation:
The answer would be A! This system was first put into place in the 1800's
The area is 32,
you can imagine it being 2 squares.
6*(8-4)
2*4
24+8 is 32
The Sahara desert is vast, large, dry, and empty of resources. This means people/armies wouldn't walk through there because it's basically suicide. This acts as a "natural barrier" because nobody would cross the desert in the first place.
Hope this helps!
Answer:
The answer is A
Explanation:
Seafloor spreading causes continental plates such as the North American Plate and the Eurasian plate to move apart in the mid-Atlantic ridge. However, the movement of the plate can cause the plates to move towards others. Eventually, when the continental plates move together they form supercontinents. The convection currents in the mantle are the driving force under the tectonic plates.
Kola Nuts sold as trade -west africa
niger one- west africa
salt- north africa
gold- south africa