Why does Denmark Vesey's quote have a particularly powerful message for slaves?

Explain why components that are naturally found in air can be considered air pollutants.

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)

What processes does carbon cycle through the biosphere?