Groundwater is found underground in the zone of a. porosity b. sediment c. saturation d. aeration

The two types of plains are coastal plains and lowland plains

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)

Given: circle a externally tangent to circle b. how many possible common tangents to circles a and b can exist? 2 3 4