Why do societies develop economic systems?

The diffusion of religion is biggest described as the process of

Does manufacturing in the midwest affect the nations economy

Banks offer services such as checking and savings accounts. what do banks do with most of the money they receive in deposits from customers? a) they loan it out to other customers. b) they spend it on new banks in other places. c) they keep it in a locked, secured vault in the bank. d) they send it to the federal reserve in washington, d.c.