please answer both questions.. thank you

PART B (20 MARKS) You have been assigned to develop an information system to store dental appointments in ABCD Clinic. After collecting the information system requirements, you need to produce the system design. The information system requirements are described as follow: The information system to be developed has three end-users: the nurse, customer, and doctor. Each user has a different process involved in the appointment. The nurse will insert available appointment slots into the system. The nurse can only insert available appointment slots for the doctors. Each available appointment slot has details such as the doctor's name and appointment time. This is because the clinic has three doctors, and each doctor has their time slot for the appointment. Once the appointment slot has been inserted, the nurse can view all the inserted appointments. The nurse can view upcoming appointments and previous appointments that have been completed. The nurse can see all the doctor's appointments. If there is a change in appointment, as there is a case such as a doctor emergency leave, the nurse can update the appointment by changing the appointment time. The second end-user of this information system is a customer. The customer will first need to view the appointment slot. The system will display available and also non-available appointment slots. Each appointment slot has a doctor's name who will be in service. If the appointment slot is available, the customer can choose the appointment slot by selecting it. Once the appointment has been made, the system will save the appointment information. The customer can view their appointment. The system will display the current and previous appointments that the customer has made. The third end-user of this information system is a doctor. The doctor can view their appointment slot. The system will display the doctor's available slot and appointments that their customer has made. The doctor can only see their appointment slot. Based on the above case study: a) Draw a Context Diagram (4 marks) b) Draw a Diagram-o (16 marks)