Which contribution did Sunni Ali make to the Songhai Empire? He united the Songhai Empire and brought about a period of peace.
He oversaw the construction of schools and universities.
He made Islam the official religion of the Songhai Empire.
He increased agriculture and introduced a new crop, cotton.

social contract theory, nearly as old as philosophy itself, is the view that persons' moral and/or political obligations are dependent upon a contract or agreement among them to form the society in which they live

there are approximately 11 million illegal immigrants living in the united states.

the argument to restrict immigration is based on the perspective of protecting the safety and employment of the american people. president trump proposes to create a wall on the border with mexico, where there is the largest influx of illegal immigrants into the country.

the liberal perspective, however, is based on the argument that the us was founded by immigrants who came to build a better life with their families. in this sense, there is a special concern with the definitive legalization of "dreamers", young people who have arrived in the country as children. another important point is the concern not to cause traumas with the separation of relatives. making immigration more open would also be a good point to stimulate diversity in the us.