Identify the business rules for the following scenario: Book. com is an online store on the Internet where customers can browse the catalog and select products of interest.

Every book has a title, ISBN, year and price. The store also keeps the author and publisher for any book.
For authors, the database keeps the name, address and the URL of their homepage.

For publishers, the database keeps the name, address, phone number and the URL of their website.
The store has several warehouses, each of which has a code, address and phone number.
The warehouse stocks several books. A book may be stocked at multiple warehouses.
The database records the number of copies of a book stocked at various warehouses.
The bookstore keeps the name, address, email-id, and phone number of its customers.

A customer owns several shopping carts. A shopping cart is identified by a Shopping_Cart_ID and contains several books.
Some shopping carts may contain more than one copy of same book. The database records the number of copies of each book in any shopping cart.

At that time, more information will be needed to complete the transaction. Usually, the customer will be asked to fill or select a billing address, a shipping address, a shipping option, and payment information such as credit card number. An email notification is sent to the customer as soon as the order is placed.