1. What is the purpose of ER modeling? 2. What is meant by cardinality? What do cardinality constraints indicate? 3. What are candidate keys? 4. Create requirements and the ER diagram for a binary relationship where each entity has several attributes, that are involved in the following relationships: a. 1:M relationship, where participation on the 1 side is mandatory and participation on the M side is optional b. 1:M relationship, where participation on both sides is mandatory C. M:N relationship, where participation on one side is mandatory and participation on the other side is optional d. M:N relationship, where participation on both sides is optional e. 1:1 relationship, where participation on both sides is mandatory 5. Create an example of an entity with a composite unique attribute and with multiple unique attributes (candidate keys)