help with history

Two: Between 1800 and the 1960s Europe and its offshoots, especially the USA, achieved economic, military, and cultural hegemony despite devastating world wars. Why did European dominance start to decline a generation after 1945?

Three:  Trace the reemergence of Asia as the center of the world economy in the late 20th and early 21st century.  Is the new global order providing a broader based of economic and political development than previous eras?