Given the following relational database schema:

Student = (SSN, Name, Major)

Course = ( CourseNumber, PrerequisiteCourseNumber, Course Title, NumberUnits)

Section = ( CourseNumber, Quarter, RoomNumber, DayTime), where DayTime is of the form MW 1:0-2:00PM.

Enrollment = (SSN,CourseNumber, Quarter, Grade)// Grade is either Null or a letter grade.

Express the following queries using appropriate SQL statements with a minimum number of operations:

a)List every two CourseNumber and their titles which have the same prerequisites.

b)List the name of every student and SSN who has completed all the courses he/she has taken and earned an A in each course, i.e. every grade is an A and no NULL value

c)List the name of every student and SSN who earned no A in any course.