1. Queries in Relational Algebra and SQL Consider a database for the basic and secondary education system (B + S) with the following attributes: - Curricular_Year = {1, 2, 3... 12} - Teaching_grade = {basic, secondary} - Nature = {public education, private education) - Type = {regular basic education, basic vocational education, secondary education, secondary vocational education, other basic} - Area = {London, Manchester, Newcastle, Southampton, Leeds) - Transitions = {approved, retained, abandoned, rejoined} And with the following tables: - students (student.ID ->name, address, contact, education_supervisor) - history (id.Fact->student.ID, school_year, curricular_year, area, id.Type, nature, transition) -types (id. Types -> id.Level) -level (id. Level) Express the query in SQL avoiding the WITH clauses, TOP and LIMIT: 1.1 Which students have more retentions than the average of all retentions the students