M:N relationship can be changed into two $1$:M relationships using a $\_\_\_\_\_\_\_\_\_\_.$ a$.$ composite entity b$.$ JOIN c$.$ SELECT d$.$ foreign key $32.$ In a M:N relationship between STUDENT and CLASS at a university, it is possible that a class may start with no students and a student may start with no classes. If a database designer is using the O symbol using the Chen model, what is the designer hoping to establish between these entities? a$.$ An optional relationship. b$.$ A cardinality figure. c$.$ A domain of possible values. d$.$ A set of optional identifiers. $33.$ A user gets an error when entering new information into a table. The error suggests the wrong values are entered in$.$ What can the user review about the table's attributes to ensure the right values are entered in$?$ a$.$ The attribute's domain b$.$ The name of the entity c$.$ The tables primary identifier d$.$ The candidate key $34.$ In the enhanced$-$entity$-$relationship, what is the collection of entities in this set classified as$?$ a$.$ object b$.$ class c$.$ schema d$.$ construct $35.$ If we are creating subtypes for a car dealership. Why would an accountant be a subtype of an employee? a$.$ because it is identifiable with employees and has unique attributes b$.$ because it only is identifiable with employees c$.$ because it is not identifiable with employees but has unique attributes d$.$ because it only has unique attributes