What was the leading cause of death during the civil war

How were returning african-american soldiers treated in american cities in 1919–1920?

What clause(s) expanded the power of the executive branch, especially relating to foreign policy?

What led to the environmental damage that caused the dust bowl? 1. desert winds emerging from the southwest 2. rotating crops every year and having fallow land 3.overplanting throughout the great plains 4.a year-long drought