Why might rome along with greece and
egypt be described as part of the mediterranean world?

The majority of the Roman empire is located around the Mediterranean, and their capitol, Rome, was located in Italy close the the Mediterranean Sea, thus by location they are part of the Mediterranean world. If you look at a map of the Roman Empire it might help explain their location on the shores of the Mediterranean. 

Abolition of slavery

Thats not a question. what do you want me to do?