Answer:
A-The Amazon acts as more of a barrier to movement
b- The Amazon is much harder to get to
c- The Amazon is surrounded by farmlands
Explanation:
The Amazon river has surroundings which are largely underdeveloped with large amount of plant life. They also inhabit lots of animal life too.The surroundings are hard to get to due to poor road network.
The Mississippi River however is found in a more developed industrial area and lacks a dense plant population with good road networks.
On the medieval world-maps it was represented only the part of the world known as the 'old world', which is consisted of Europe, Asia and Africa. Before the big discoveries, people living in this continents had knowledge only of this part of the world, while South and North America, Australia and Antarctica where still unknown to them, thus they are missing in the world-maps of this period.
They are electromagnetic waves because mechanical waves have to be physically created by something, while electromagnetic waves are just emitted without any effort or force.
That would be the Himalayas and have the highest mountain range in the world.
They are what cause earthquakes, if the plates go seperate ways they cause the earth to shake