answer quick please.

Q4. Draw use case model and class diagram for the case given below. (20 Marks) The BOOK BUYING SYSTEM is a web-based system through which one will be able to buy the stationary and related materials through online mode i.e. here the User can directly buy the products from home or from anywhere via internet using mobile phones. The system provides a well-defined user interface. Users can register themselves easily. User can also login as a guest. The user will visit the website and will see a wide range of the material arranged in respective categories with the set of filters etc. He will select the category of stationary item: a whole list of same category item will be shown up. He will view their details like price, quality, size etc. And will select desired materials. Then he will have the option to order the material with specifying the number of items and add it to cart and provide address to deliver the order. The order will be registered with the system and then the shop's vendor will collect items from the racks of the shops according to the order. The user can also modify his order placed in cart while reviewing cart and can add or delete items. Before accessing the cart, he must have to sign up and then sign in for confirming and placing the order. If he is already logged in, then he can check out. Once the order is finally placed, the system will produce a receipt detailing a user's purchase information including name of user, item purchased, cost of each item and total cost. He offered an adequate checkout mechanism. Confirmation email will be sent to him. He can pay the bill on cash on delivery after order being received and can also pay the bill Online. At last, he will get notification or message about how long it will take to deliver the order (depending upon how far the location is). In the end, user will be offered a friendly feedback mechanism, so that users can give feedback for the product or service which they have purchased and can provide their valuable ratings regarding application and services. The website will have an admin who will have access to all the information present on the website. Admin will use this application to give them access to the person who wants to purchase goods or items. He will add, edit, and delete all information concerning stationery store, list of items, categories, description, author, quality and prices through excel file. All data will be maintained in the database. The system will get updated automatically when there is any modification made by admin. He can also generate and view several types of reports. Whenever user want to purchase items or goods, he just needs to send the request to the admin, and he will approve his request by looking at the requirement and information provided by him on the website a