I need help please. Can you answer and explain the questions?

Use the following tables that depict that an author can write many books, and a book can have many authors. Each book has only one

publisher, but a publisher can publish many books. An author can attend many book signings. Each book signing is done by only one

author. The primary keys to consider are indicated.

SIGNING $($primary key: SIGN ID$)$

WRITES $($composite primary key: AU$\_$ID$,$ BOOK$\_$ID$)$

AUTHOR $($primary key: AU$\_$ID$)$

BOOK $($primary key: BOOK$\_$ID$)$

PUBLISHER $($primary key: PUB ID$)$

$1.$ Does the PUBLISHER table have entity integrity? Why or why not?

$2.$ Does the AUTHOR table have entity integrity? Why or why not?

$3.$ Does the WRITES table have entity integrity? Why or why not?

$4.$ Does the SIGNING table have referential integrity in its relationship with AUTHOR? Why or why not?

$5.$ Does the PUBLISHER table have referential integrity in its relationship with BOOK? Why or why not?

$6.$ Does the WRITES table have referential integrity in its relationship with BOOK? Why or why not?

$7.$ Create the table that would result from an Equijoin of SIGNING$-$join$-$AUTHOR.

$8.$ Create the table that would result from a RIGHT Outer Join of BOOK$-$join$-$PUBLISHER.