Please answer c

Consider the following relations. A student may take many courses. A course must be taken by at least one student. A student may take the same course in multiple years 2. student (studentID, studentFullName course (courselD, courseName) takes (studentID, courselD, year) a) [S points] Identify the primary and foreign keys in each of the relations b) S points each) Explain using your words what the following expressions do, and show the output schema for each: year > 2005) (takes) bd student ?(year 2005) (takes student) o m(studentiD, studentFullName, courselD) (takes Dd student) o c) [ (5 points each] Write the expressions in the relational algebra for the following queries: o Find the name of the students who took a course in 2009 Find the name of the courses that any students named "John" took in 2008 o Find the ID of the students who took a course in 2008 and retook that course in 2009