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 the name and major of every student who has only taken courses that meet MW afternoon (12 or after).

b)List the name and major of every student who has taken all the courses that meet MW afternoon.

c)List the name and major of every student who has not taken any course that meets MW afternoon.