They really help in the process of Africa's state building, creating commercial networks between parts of the continent, and introducing literacy ( especially on northern part of Africa)
They also controlled the sea route between Asia and Africa and managed to maintain the relationship between Africa and the middle east
Answer:
Explanation:
Simplify -3\times -5−3×−5 to 1515.
15=-2\times -20
15=−2×−20
2 Simplify 2\times -202×−20 to -40−40.
15=-(-40)
15=−(−40)
3 Remove parentheses.
15=40
15=40
4 Since 15=4015=40 is false, there is no solution.
No Solution
P waves can travel through liquid and solids and gases, while S waves only travel through solids. Scientists use this information to help them determine the structure of Earth.
S waves have a larger amplitude than P waves and cause the ground's surface to move both vertically and horizontally, making them more dangerous. Surface waves, which move slowly, are the last to arrive. P waves leave the earthquake first and go the furthest. Rock oscillates perpendicular to the direction of wave propagation in S or shear waves. In rock, S waves typically move at a pace of roughly 60% that of P waves, and they always come after the latter. Points of solid media move back and forth perpendicular to the wave's direction of propagation due to S waves, also known as shear or transverse waves. As the wave passes, the medium is sheared first in one direction and then in the opposite direction.
To learn more about P-waves and S-waves click the link below:
brainly.com/question/29334933
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