What gas dominated earth’s first atmosphere?

In the developed world, describe the changing role of women in agriculture.

Read the article titled "trans-saharan migration routes to north africa and the eu: historical roots and current trends." why do tens of thousands of sub-saharan africans try to cross the mediterranean each year? how are these refugees commonly portrayed? (site 1)

Name the two rivers that run through the fertile crescent. how were the rivers both positive and negative to societies of the fertile crescent?