Consider the ERD below. Which of the following statement is$/$are true about th ERD? Select all that applies:

a$)$ An INSTRUCTOR may be a DEAN

b$)$ An INSTRUCTOR, may have more than one DEGREE

c$)$ A STUDENT may exist without being in a DEPT.

d$)$ Each instance of INSTRUCTOR can be identified by the Degree attribute.

e$)$ The GPA of a STUDENT is a derived attribute.

f$)$ A COLLEGE must have at least one DEPT

S$)$ STUDENT has an attribute that is a composite attribute.

The DEAN of a COLLEGE must be an INSTRUCTOR.

A DEPT may exist without employing an INSTRUCTOR

There are $6$ identifying relationships in the ERD.

k$)$ INSTRUCTOR may exist without being employed in a specific DEPT.

A DEPT may have at most only one Dphone.

m$)$ Each DEPT must have a chair always.

n$)$ A COURSE may have more than $1$ INSTRUCTOR.

o$)$ A COURSE needs information about the DEPT to uniquely identify its instances

Each instance of SECTION can be identified by the SecNO attribute.

An INSTRUCTOR must teach at least one course.

r$)$ DEPT must offer at least one COURSE

s$)$ A DEPT may exist without having STUDENT.

A COLLEGE must a DEAN and only $1$ DEAN is allowed.

An INSTRUCTOR may teach several courses

Each instance of COURSE can be identified by the CCode attribute.

W$)$ STUDENT has an attribute that is a multi$-$valued attribute.

W$)$ STUDENT has an attribute that is a multi$-$valued attribute.

x$)$ A SESSION may be taught by more than $1$ INSTRUCTOR

y$)$ A STUDENT may take several SECTION at the same time.

An INSTRUCTOR can work for only one DEPT