Answer:
Mansa Musa inherited a kingdom that was already wealthy, but his work in expanding trade made Mali the wealthiest kingdom in Africa. His riches came from mining significant salt and gold deposits in the Mali kingdom. Elephant ivory was another major source of wealth.
Laws are no longer strictly enforced.
One of the most important was climate changes. As climate changed, nomads had to find new places to migrate to which led to people going to areas that were uninhabited before. Another was the development of agriculture which more or less ended the nomadic way of life when people started settling.
