Question 2 Carefully read the following event and scenarios. Turkish Airlines : Flight Reservation System Turkish Airlines wants an online system that will enable potential passengers to check flight timetables and allow flights to be booked and paid for using a credit or debit card. The new online system should be able to handle three categories of potential passengers: adults, who pay full fare, children (under the age of 12), who pay the half fare and frequent flyers, who get a 15% discount. To make a booking, a visitor will use the system to select their preferred departure and destination cities where the airline operates. Next, the visitor will choose the departure and return dates. Then a list of all the available flights will be displayed, including fares for each flight. After that, the visitor should be able to select a flight from the list. Of course, the system will not display any "fully booked" flights. The system will then prompt the visitor to enter the details of all intended passengers (e.g. name, telephone number, postal address, date of birth, and e-mail address). Additional information like seating preference (aisle or window) and meal preferences (vegetarian) may also be entered. Frequent flyers will have to enter a valid 10-digin PIN to get the discount. When the visitor has confirmed the booking details, the system will provisionally book the seat(s) so that no other visitor can make a booking for the same seat(s) on the same fight. Then the visitor will be prompted to input the payment details such as cardholder name, card number, issue date, etc. The system will then transfer control to a separate secure server for credit status confirmation. If payment is authorized the system will book the flight, mark the seat(s) as "sold" and automatically issue an "e-ticket" confirming flight details to the passenger. Once payment has been received, cancellations cannot be made. If the secure server rejects the payment, the entire transaction will be rolled back, and the seat(s) will become available to other visitors. From the above scenarios, (a) Illustrate an Activity Diagram for Flight Reservation System of Turkish Airlines. (37 marks) (b) Build the Use-case Diagram for Turkish Airlines Flight Reservation System. (23 marks)