How successful do you feel mark twain is in creating the character Jim?What was he like? Real?
Are you being asked to give your opinion regarding the effectiveness of Twain's writing in portraying Jim as a real person, or are you soliciting opinions from eNotes editors?
If you are supposed to be presenting your feelings, then you need to look for support for your opinions in the parts of the book that explain Jim's character, appearance, and actions. Do you identify with the reactions Jim had when he discovered Huck hadn't been drowned, when he was afraid of being discovered, when he was mourning being separated from his family? If you feel these were effectively written to create the impression of an actual person with emotions and feelings and motivations based on potentially real situations, then you would feel that Twain was successful in creating the character.