1) Consider the database schema on the relations (where key attributes have been underlined): COURSES(Number, Faculty, CourseName) STUDENTS(Number, Surname, FirstName, Faculty) EXAMS(Student, Course, Grade, Date) NOTE: relation EXAMS stores the registration number (attribute Student) of students that passed the exam for a given course (attribute Course is the number of course, not the name of the course), the grade and the date of the exam. a) Formulate in tuple relational calculus the query that retrieves the grades (5marks) achieved in exams that took place on 10/02/15 b) Formulate in relational algebra the query that retrieves the student number and grade of the students in the Faculty of Science that passed the exam for a (15marks) f Siene sed the exm course with CourseName Algebra c) Describe the standard three-level architecture for a DBMS. (5marks) 1) Consider the database schema on the relations (where key attributes have been underlined): COURSES(Number, Faculty, CourseName) STUDENTS(Number, Surname, FirstName, Faculty) EXAMS(Student, Course, Grade, Date) NOTE: relation EXAMS stores the registration number (attribute Student) of students that passed the exam for a given course (attribute Course is the number of course, not the name of the course), the grade and the date of the exam. a) Formulate in tuple relational calculus the query that retrieves the grades (5marks) achieved in exams that took place on 10/02/15 b) Formulate in relational algebra the query that retrieves the student number and grade of the students in the Faculty of Science that passed the exam for a (15marks) f Siene sed the exm course with CourseName Algebra c) Describe the standard three-level architecture for a DBMS. (5marks)