$($b$)$ Identify possible objects in the following systems and develop an object$-$oriented

design for them. You may make any reasonable assumptions about the systems when

deriving the design:

i$.$ A group diary and time management system is intended to support the timetabling

of meetings and appointments across a group of co$-$workers. When an

appointment is to be made that involves a number of people, the system finds a

common slot in each of their diaries and arranges the appointment for that time. If

no common slots are available, it interacts with the user to rearrange his or her

personal diary to make room for the appointment.