Why did the conflicts and crises of the first half of the 20th century become global in nature?

How many citizens of mexico does it take to equal the ecological footprint of the average citizen of the united states? it takes nearly three mexican citizens to equal the ecological footprint of the average u.s. citizen. it takes about 12 mexican citizens to equal the ecological footprint of the average u.s. citizen. it takes just over eight mexican citizens to equal the ecological footprint of the average u.s. citizen. two citizens of mexico equal the ecological footprint of one average citizen of the united states. they are essentially equal?

When conducting research for forming a hypothesis, which practice should historians follow?

What is the main purpose of "falling action" in a story?