In which scenario would instant messaging be more useful than other forms of communication?

jane, joey, and rebecca are assigned to work on a project together. jane has a different schedule and needs to be updated on what joey and rebecca accomplished today.

sue and shae are waiting for roy at the movie theater. both of them are carrying cell phones with internet connectivity.

serena and sharon are doing their math homework in their own homes. they need from each other to complete the task.