2. Question for Chapter 5: Relational Algebra and SQL Suppose table USER has attributes email, name, address, and householdSize, where email being the primary key (a) Express in relational algebra the query that finds all pairs of users where the two people both claim to have a household size 2 and have the same address and returns their names and the common address (b) Express the above query in SQL (c) Write in SQL the query that finds the users whose household size is at least 50% more than the average household size and returns their name and household size, sorted by household size. (Hint: decompose the problem into subproblems, and you may use a view to capture a intermediate result.) d) Write in SQL the query that finds all users each having a household size different from the total number of users having the same address as him or her. (Hint: again, decompose the problem into subproblems, and you may use a view to capture a intermediate result.)