An index is clustered, if

Given the basic $$ER$$ and relational models, which of the following is INCORRECT?

Consider a relation table with a single record for each registered student with a single record for each registered student with the following attributes.
$$1.$$ $$Registration$$ $$Num:$$ Unique registration number of each registered student.
$$2.$$ $$UID :$$ Unique identity number, unique at the national level for each cityzen.
$$3.$$ $$BankAccount_Num:$$ Unique account number at the bank. A student can have multiple accounts or joint accounts. This attribute stores the primary account number.
$$4.$$ $$Name:$$ Name of the student
$$5.$$ $$Hostel$$ $$Room:$$ Room number of the hostel.

Which of the following options is INCORRECT?

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