Consider the entities 'hotel room', and 'person' with a many to many relationship 'lodging' as shown below

If we wish to store information about the rent payment to be made by person(s) occupying different hotel rooms, then this information should appear as an attribute of

The following table has two attributes $$A$$ and $$C$$ where $$A$$ is the primary key and $$C$$ is the foreign key referencing $$A$$ with on-delete cascade.

The set of all tuples that must be additionally deleted to preserve referential integrity. When the tuple $$(2,4)$$ is deleted is:

Let $${E_1}$$ and $${E_2}$$ be two entities in an E-R diagram with simple single-valued attributes, $${E_1}$$ and $${E_2}$$ are two relationships between $${E_1}$$ and $${E_2}$$, Where $${E_1}$$ is one-to-many and $${E_2}$$ is many-to-many. $${E_1}$$ and $${E_2}$$ do not have any attributes of their own. What is the minimum number of tables required represent this situation in the relation model?

The set $$\left\{ {1,\,\,2,\,\,4,\,\,7,\,\,8,\,\,11,\,\,13,\,\,14} \right\}$$ is a group under multiplication modulo $$15$$. The inverse of $$4$$ and $$7$$ are respectively: