Assume the School database shown in the Appendix. Write the following queries in $($I$)$ relational algebra and $(2)$ SQL$.$ State your as sumptions if the semantics are not clear.

STUDENTS$($student$\_$id$,$ first$\_$name, last$\_$name, email, najor$\_$code. class$\_$year$)$ COURSES$($course$\_$id$,$ course$\_$name, course$\_$description, credits, department$\_$code$)$ ENROLLMENTS$($student$\_$id$,$ course id$,$ semester, grade$)$

MAJORS$($nujor$\_$code, major$\_$nane. department$\_$code$)$

DEPARTMENTS $($department$\_$code. department$\_$name$)$