a.) What is the purpose of developing use cases during systems analysis? (3marks) b.) Describe two ways to handle a situation in which there are a large number of use cases. (2marks) c.) Create a set of use cases for the accompanying dentist office system, but do not bother to identify the steps within each use case. When new patients are seen for the first time, they complete a patient information form that asks for their name, address, phone number, and brief medical history, which are stored in the patient information file. When a patient makes a call to schedule a new appointment or change an existing appointment, the receptionist checks the appointment file for an available time. Once a good time is found for the patient, the appointment is scheduled. If the patient is a new patient, an incomplete entry is made in the patient file; the full information will be collected when the patient drives for the appointment. Because appointments are often made far in advance the receptionist usually mails a reminder postcard to each patient two weeks before the appointment. (10marks) d.) Draw a level 0 data flow diagram (DFD) for the dentist office system. (5marks)