Influential event in the 21st century

What single event in the period of the 20th century you believe will have the greatest influence over the 21st century?

Market Revolution

Explain the impact of the market revolution on American workers.

World Civilization

Identify and discuss what you think is the single most important development in human evolution from the advent of Australopithecines through the beginning of agriculture is. Please be brief and straight to the point so that I can better understand. Narrow it down in 2 paragraphs. Thanks so much. I really struggle in history.

Help with comparing and contrasting these areas is given.

This posting discusses a specific characteristic of the river valley civilizations established along the Nile, the Tigris and the Euphrates, the Indus, and the Yangzi and the Yellow Rivers that distinguished these civilizations from earlier Neolithic communities and cultures.

Reconstruction

What was the greatest success of Reconstruction? Would you agree with historians who argue that even if Reconstruction failed at the time, it laid the foundations for the later successes of the civil rights movement?