How did trade early africans to develop advanced societies

The correct answer is: systems of weights and measures.

Explanation

The trade helped early Africans to develop advanced societies through the use of efficient systems of weights and measures. In fact, this put Africans in contact with other people's ideas which led to a bigger and faster development of their society.

answer: musical connotation

leonard b. meyer (1918-2007) was an american composer, author and philosopher. his work emotion and meaning in music is perhaps the first major treatise on music. it is a philosophical and psychological work, greatly influenced by koffka (one of the major proponents of gestalt psychology). his work deals with the problem of musical meaning and musical communication.