Consider a relational database containing the following schemas. Catalogue 24865 ne pre cost 81 PI SI P2 SI P3 52 PA 200 82 53 PI 250 S3 P2 150 53 S3 PA 250 Suppliers SI M/s Royal furniture M/s Balaji furniture S3 M/s Proman furniture Delhi Bangalore Chennai Parts po prame part spec PI Table Wood Chair Wood Table Steel 14 Almirah Steel P5 Almirah Wood The primary key of each table is indicated by underlining the constituent fields. SELECT a.sno, na FROM Suppliers, catalogue WHERE ..sometne AND cost > SELECT AVG (cost) FROM Catalogue WHERE po- 'P4 GROUP BY pro) The number of rows returned by the above SOL query is