They came because of Rinderpest. Before coming to South America, Africans in Africa depended on cattle such as cows to thrive. But Rinderpest brought to Africa by foriegners began to spread, and the cattle started to suffered from fevers, inflammation in the brain and dysentery. They also had major problems with Europeans and their industries. So they decided to settle in South America.
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Answer:
Porosity
Explanation:
Porosity is defined as the total percentage of pore spaces that are present within a rock. These spaces are found between the rock particles and fractures and are mostly filled with fluid mixture or water. It is the ratio between the total pore space in a rock to the total volume of the rock. It is mainly calculated in terms of percentage.
Porosity is directly affected by sorting. Well-sorted rocks indicate high porosity but poorly-sorted rocks indicate low porosity. Some of the examples of rocks exhibiting high porosity are limestone, shale, and sandstone. Rocks with low porosity include granite and mudstone.
As in 2009, there are approximately 20,000 cities or metropolitan areas in the United States.
