Write the relational algebra expressions for:

Authors(Auld, AuName, AuPhone) Books(ISBN, Title, Publd, Price) Publishers(Pubid, PubName, PubPhone) BookAuthor(ISBN, Auld) A) Find the titles of all books in our library. B) Find the titles of all books with a price greater than $35 C) Find the names of all authors who have been published by Big House. D) Find the titles of books authored by Shakespeare or by Austen. E) Find the names of authors who have published at least two books F) Find the names of authors with some book published by Big House and some book published by Small House G) Find the names of authors who have been published by every publisher H) Find the authors who have not had a book published by Alpha Press