Part $2$: Relational operator and relational algebra $(18$ points$)$

$1.$ Consider the following collection of relation schemes: $(6$ points$)$

Student $($studentID$,$ nationality$)$

Clubs $($studentID$,$ clubname$)$

a$.$ Find all the students who are in any one of the clubs that Carlos $($studentID $=8388)$ is in$.$

b$.$ Find all the students who are in at least one of the clubs that Carlos $($studentID $=8388)$ is in$.$