Explanation:
In Africa the climate is very harsh
To trade sometimes people have to go very far distances and cross many different climate zones
For example in the desert climate zone, temperatures in the day can get very hot. At night the temperatures can drop below zero.
The harsh climate can affect how fast it will take for traders to get from one place to another. The climate can also affect the amount of goods or kinds of goods the traders can bring or purchase.
The differences in how the war affected each nation, with the US having less destruction and casualties compared to the Soviet Union is your best answer.
Another reason is the fact that they used two seperate types of government, and each tries to impose it's own kind on other countries in an effort to be able to be the "leader of the world".
hope this helps
I believe the answer is education.
Abolitionists
The abolitionist movement was an organized effort to end the practice of slavery in the United States. The first leaders of the campaign, which took place from about 1830 to 1870, mimicked some of the same tactics British abolitionists had used to end slavery in Great Britain in the 1830s