Consider the following relations: Album (albumId: integer, title: string, artistId (FK): integer) Artist (artistId: integer, name: string) Composer (artistId: integer, name: string) Singer (artistId: integer, name: string) Write the following queries in relational algebra. (1) Find all the titles of the albums. (2) Find all the tuples whose albumId is 2 . (3) Rename the relation Artist to Art and attributes to artId, title. (4) Find all the tuples that are either an Artist or a Composer. (5) Find the tuples of Artists who are not a Composer. (6) Find the tuples of people who are Composer and a Singer at the same time. (7) Find the titles of albums created by the artist 'Black Sabbath