There can be numerous challenges but the biggest are sickness, lack of proper food and drink, increase in pollution in the area, and increased death due to these factors, Hope this helped! ^-^
The Louisiana Purchase treaty is important document because it shows the extent to which the United States was claiming land westward.
All the branches are Theravada Buddhism, Mahayana Buddhism, and Vajrayana Buddhism.
The main two are Theravada Buddhism and Mahayana Buddhism I believe.
Hope this helps! - Kana
