1. Whether or not an instance of an entity class must participate in a relationship with another entity class is indicated by what in the E-R model? 2. How are entity classes represented in the E-R model? 3. What is the difference between and entity (class) and an entity instance? 4. Given the following excerpt of an E-R model: has Entity A O 17 Entity B Fully describe the relationship between Entity A and Entity B including the degree of the relationship and its cardinalities. 5. Given the following excerpt of an E-R model: has Entity A Entity B You are informed that one instance of Entity 8 must be related to one and only one instance of Entity A, and one instance of Entity A may be related to many instances of Entity B. Complete the E-R diagram using the Crow's Foot style E-R Model 6. Given the following traditional E-R model: is_assigned DEPARTMENT HO EMPLOYEE Fully describe the relationship between the entities. Redraw the E-R diagram to include suitable attributes. Ensure that you include at least one: composite attribute, optional attribute, derived attribute, and multivalued attribute. 7. ISM Inc is a bookstore. Create the E-R diagram for the bookstore based on the following requirements ISM Inc's database will keep track of the following: For each book a unique ISBN, title, summary date of publication, and page count For each format: a unique format name, and the price for that format . For each author a unique author identifier, author full name composed of first and last name). multiple pseudonyms used by the author (if any). date of birth, age, and number of books published (derived) For each customer. a unique customer identifier, as well as their name (composted of first and last name), multiple phone numbers (if any), and multiple email addresses (if any) A book must be written by an author but may be written by multiple authors. An author may have written one or more books (an author must have written a book to be tracked) A book has multiple formats, and each format is specific to one book. There can be multiple formats with the same format name, but for a particular book, each format name will be different A book does not have to have been purchased by a customer but may have been purchased by many customers. A customer may have purchased one or more books (a customer must have purchased a book to be tracked). For each book purchase we must track the date of purchase, and the quantity purchased. 8. Investco Scout is an investment research company. Create the ER diagram for the Investco Scout Funds Database, based on the following requirements. The Investco Scout Funds Database will keep track of investment companies, the mutual funds they manage, and securities contained in the mutual funds. . For each investment company, Investco Scout will keep track of a unique investment company identifier and a unique investment company name as well as the names of multiple locations of the investment company. For each mutual fund, Investco Scout will keep track of a unique mutual fund identifier as well as the mutual fund name and inception date. . For each security, investco Scout will keep track of a unique security identifier as well as the security name and type. Investment companies can manage multiple mutual funds. Investco Scout does not keep track of investment companies that do not manage any mutual funds. A mutual fund is managed by one investment company. A mutual fund contains one or many securities. A security can be included in many mutual funds. Investco Scout keeps track of securities that are not included in any mutual funds. For each instance of a security included in a mutual fund, Investco Scout keeps track of the amount included. 9. AMAZE-ONE.COM is setting up a database for their new website to record sellers and their products. For each seller, you will need to record their name, contact email, and postal address. For each product, you will need to record its name, price, and the quantity in stock. You can assume that for a product to be listed, it must be sold by a seller. You can also assume that a new seller may not have listed any products as yet. Using the Crow's foot model draw an E-R diagram to represent this information. Be sure to indicate your identifiers and state any and all assumptions clearly