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.
Im not really good with essays,but i can give you an idea.
I think the best way to learn things is to find an interest in it and continue doing some research on it until you have a good understanding of it.Thing like a new sport or experiment