It started when we were younger you were mine my boo
The two factors, Temperature and Pressure, have the greatest influence on the state of each of Earth's layers.
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The Sahel is located in Africa. It is the region in Africa that transitions from the Sahara to the Sudanian Savanna. It stretches across in the region from the West of Africa to the East and includes parts of Senegal, Mauritania, Mali, Burkina Faso, Algeria, Niger, Nigeria, Chad, Sudan, South Sudan, Eritrea, CAR, Cameroon, and Ethiopia.