Why would South America and Africa have no urban regions

Because the total area of those two countries are too massive to populate and some of the environments are inhospitable.

Explanation:

because the two continents have most of their population in rural places and most of the countries in those 2 regions have a smaller GDP and economic growth so they don't really invest into a more urban society. another reason is a lot of those countries owe a lot of debt to the world bank. But most importantly their culture is more focused on livestock and farming  

Explanation:

the anasazi indians were real pioneers and created roads and irrigation systems for watering their crops. they were also great architects and the cliff dwellings are one of their biggest achievements.

explanation:

q1: artillery

q2: simon bolivar

q3:   their workers and farmers demanded a return to spanish rule.

q4: drafted new constitutions

q5: oligarchies have replaced monarchies