Note 1: software engg based question : Note 2 :kindly send me clear and exit answer

Question No. 2. (20+10=30) "Suppose you are approached by a client who is expanding his business of secondhand bookshop. In order to attract more clients, he wants you to develop an online system where all the registered users can sell and purchase their old books. The system will contain all the basic functionalities which can be found in any e-commerce web applications i.e. book search based on name, book type and price etc., adding to shopping cart, and uploading books information for selling. All the payments can be made either by using online payments methods like banks, credit cards etc. or by cash on delivery". a. Consider the above scenario for a second hand book shop. How would you develop software by using Spiral model approach? b. Draw a graphical user interface (GUI) for the software system that describe above