create ERD for the following:

1. (30 Points) A real estate firm lists properties for sale. The firm has a number of sales offices in several states. For each office, it is important to know the location and length of time the office has been open. Each sales office has several employees. The company wants to track employee names, addresses, and company ID numbers. An employee can only work for one sales office. For each sales office, there is always one employee assigned to manage the office. An employee can only manage the office to which he or she is assigned. Attributes of each property for sale include the property number, location (address, city, state, and zip code), and listing date. Each unit of property must be listed with one (and only one) of the sales offices and sales offices each generally have multiple listings. Each property has one or more owners. For each owner, we need to know the owner's name, address, and email address. An owner can own multiple properties and some properties have join ownership (multiple owners). Given this, it is important to know how much of each property is owned by each owner. Draw an ERD that models these data requirements. ----------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ----- Assumptions: a) Does every employee have a home office? Where is this shown? b) Does every office have to have a manager? Where is this shown? 2. (35 Points) A nonprofit organization depends on a number of people for its successful operation. The organization must track, for each person, name, address, and phone number. People can be classified into three categories: employees, volunteers, and donors. Each person can be in multiple categories (e.g., a volunteer can also be a donor). For employees, it is important to capture their date hired. In order to know how best to utilize volunteers, for each volunteer the organization tracks which skills the volunteer possesses (e.g., accounting, sales, lion taming) and what level of proficiency the volunteer possesses for that skill (on a scale from 1 to 10). Donors donate items (including money) to the nonprofit organization. For each item, we need to know what it is and its value. Draw an ER diagram that addresses the data needs of the organization. ------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ----- Assumption: a) Do we treat each donated item as a unique donation or can multiple donors donate the "same" item? 3. (35 Points) The H.I. Topi School of Business operates international business programs in 10 locations throughout Europe. The school had its first class of 9,000 graduates in 1965. The school keeps track of each graduate's student number, name when a student, country of birth, current country of citizenship, current name, current address, and the name of each major the student completed (each student has up to two majors). To maintain strong ties with its alumni, the school holds various events around the world. Events have a title, date, location, and type (e.g., reception, dinner, or seminar). The school needs to keep track of which graduates have attended which events. For an attendance by a graduate at an event, a comment is recorded about information school officials learned from that graduate at that event. The school also keeps in contact with graduates by mail, e-mail, telephone, and fax interactions. As with events, the school records information learned from the graduate from each of these contacts. When a school official knows that he or she will be meeting or talking to a graduate, a report is produced showing the latest information about that graduate and the information learned during the past two years from that graduate from all contacts and events the graduate attended. State any additional assumptions you believe you have to make in order to develop a complete diagram. (Hint: you need a lot of entities for this problem.) ----------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ---------- Also: a) How could we keep address history (i.e., what changes would you make to the ERD)? b) How could we keep name history? 1. (30 Points) A real estate firm lists properties for sale. The firm has a number of sales offices in several states. For each office, it is important to know the location and length of time the office has been open. Each sales office has several employees. The company wants to track employee names, addresses, and company ID numbers. An employee can only work for one sales office. For each sales office, there is always one employee assigned to manage the office. An employee can only manage the office to which he or she is assigned. Attributes of each property for sale include the property number, location (address, city, state, and zip code), and listing date. Each unit of property must be listed with one (and only one) of the sales offices and sales offices each generally have multiple listings. Each property has one or more owners. For each owner, we need to know the owner's name, address, and email address. An owner can own multiple properties and some properties have join ownership (multiple owners). Given this, it is important to know how much of each property is owned by each owner. Draw an ERD that models these data requirements. ----------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ----- Assumptions: a) Does every employee have a home office? Where is this shown? b) Does every office have to have a manager? Where is this shown? 2. (35 Points) A nonprofit organization depends on a number of people for its successful operation. The organization must track, for each person, name, address, and phone number. People can be classified into three categories: employees, volunteers, and donors. Each person can be in multiple categories (e.g., a volunteer can also be a donor). For employees, it is important to capture their date hired. In order to know how best to utilize volunteers, for each volunteer the organization tracks which skills the volunteer possesses (e.g., accounting, sales, lion taming) and what level of proficiency the volunteer possesses for that skill (on a scale from 1 to 10). Donors donate items (including money) to the nonprofit organization. For each item, we need to know what it is and its value. Draw an ER diagram that addresses the data needs of the organization. ------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ----- Assumption: a) Do we treat each donated item as a unique donation or can multiple donors donate the "same" item? 3. (35 Points) The H.I. Topi School of Business operates international business programs in 10 locations throughout Europe. The school had its first class of 9,000 graduates in 1965. The school keeps track of each graduate's student number, name when a student, country of birth, current country of citizenship, current name, current address, and the name of each major the student completed (each student has up to two majors). To maintain strong ties with its alumni, the school holds various events around the world. Events have a title, date, location, and type (e.g., reception, dinner, or seminar). The school needs to keep track of which graduates have attended which events. For an attendance by a graduate at an event, a comment is recorded about information school officials learned from that graduate at that event. The school also keeps in contact with graduates by mail, e-mail, telephone, and fax interactions. As with events, the school records information learned from the graduate from each of these contacts. When a school official knows that he or she will be meeting or talking to a graduate, a report is produced showing the latest information about that graduate and the information learned during the past two years from that graduate from all contacts and events the graduate attended. State any additional assumptions you believe you have to make in order to develop a complete diagram. (Hint: you need a lot of entities for this problem.) ----------- INSERT SOLUTION HERE, THEN REMOVE THIS TEXT ---------- Also: a) How could we keep address history (i.e., what changes would you make to the ERD)? b) How could we keep name history