Consider the relation Employee$\_$Department in the following Figure.

Ename

Pnum

Bdate

Dnumber

Department

Dhomepage

John B

$100$

$1965-01-03$

$2$

Computing Science

www$/$it$/$cos

Smith L

$105$

$1955-10-12$

$2$

Computing Science

www$/$it$/$cos

James P

$110$

$1962-03-03$

$1$

Computer Systems

www$/$it$/$sys

Anna R

$111$

$1976-11-23$

$4$

Scientific Computing

www$/$it$/$sci

Pia S

$112$

$1964-10-10$

$4$

Scientific Computing

www$/$it$/$sci