<span>B. they needed access to bodies of water for trade
Water and aquatic access was necessary for water as well as access to trade.
Hope this helps :)</span>
Subsoil: This layer has normally less organic matter than the A horizon, so its colour is mainly derived from iron oxides. Iron oxides and clay minerals accumulate as a result of weathering. In a soil, where substances move down from the topsoil, this is the layer, where they accumulate.
Note: This information has been taken out of a website.
<h2>Answer: D. Rayleigh wave
</h2>
Rayleigh waves are a type of surface acoustic wave that causes particles on the surface of solids to travel along an elliptical path in the vertical plane that contains the direction of wave propagation.
These waves include longitudinal (P wave) and transverse (S wave) movements whose amplitude decreases exponentially as the distance from the surface increases.
This means Rayleigh waves are generated by the interference between the P and S waves on the surface of the Earth.
Why might a post classical civilization want to conquer Egypt and the Nile River Valley? It's fertile land provided the foundation for the first human civilizations and its access to the Persian Gulf and location between Europe, Asia, and Africa made it a center of trade.
