Why did the important leaders not attend the convention?

Following archduke franz ferdinand's assassination, austro-hungarian leaders: a. aided the ottoman empire in its campaign to keep serbia under its control. b. executed nearly all prominent serbs living in austria-hungary c. threatened to invade serbia if serb leaders did not agree to a set of strict demands. d.. formed an alliance with great britain to protect austria-hungary from future attacks.

World war 2 was caused, in part, by which of these factors?

What do the differing approaches of booker t. washington and w.e.b du bois suggest about their views of american society?