Why does malaria occur only in the poor countries?

It typically occurs in regions with tropical or subtropical temperatures, and thus is prevalent year round. In poorer countries, there are less resources to immunize or prevent the disease from spreading. There is also usually a higher density of people in lower socio-economic areas, so transmission is easier and harder to control.

Its in the national history museum and you can't se the original because its locked away in a vault 

Answerdistinguish between the mercalli scale and the richter scale;