What was a primary motive behind the implementation of sharia in islamic empires beginning in the 8th century

Ineed to try to get this right so i can get a good grade so can someone me

The california gold rush: actually had only a small impact on california’s population because its rich farmlands already attracted thousands of new settlers each year. attracted almost equal numbers of men and women. resulted in laws that discriminated against “foreign miners.” made considerable wealth for average miners because gold mining demanded no real investment of capital. hurt the development of san francisco because gold discoveries shifted interest to areas outside of town.

Why did jefferson make the louisiana purchase?