The Moroccan invasion was the direct factor that caused the Songhai kingdom to fall. Many other factors such as incompetent leaders, and loads of rebellions caused this too.
Typically their sale lasts for four weeks.
What can a producer gain by specializing? Absolute advantage
When someone specializes in their field, they being an expert in that subject. Absolute advantage is the ability of a person or group to carry out an economic activity better than another. If someone focuses on it and specializes in one area, they are more likely to create an absolute advantage in that area.