..... Q3. (Constraints): Declare the following referential integrity constraints for the SIS database: a) If some tuples are deleted from STUDENT relation, the tuples in ENROLLMENT, that contain the deleted StdID number will be deleted. Also the system will update the Std D number in ENROLLMENT when an update is done in StdID in the Student relation. Hint: this constraint should be defined by modifying the constraint using ALTER TABLE statement Copy the answer from SQL SERVER and paste it below: ALTER TABLE b) If the student's proficiency is less than 90 then the student should pay (i.e., payment value is: yes) otherwise the student will not pay (i.e., payment value is: no). Hint: this constraint should be defined by modifying the constraint using ALTER TABLE statement. Copy the answer from SQL SERVER and paste it below: ALTER TABLE