$2.(10$ points$)$ Consider the following database schema$$Flight $($Source$,$ Destination$)$Hub $($City$)1(,)$:$(,),(),(,),()2(,)$:$(,),(),(,)($a$)(5$ points$)$ Use the conjunctive query containment algorithm to show that $12($b$)(5$ points$)$ Unfold the following query $3(,)$:$1(,),2(,)$