Consider entity type Employee with attributes empNumber (this is unique), empName, and the year when he/she was hired. An employee can either be a technical employee, a marketing employee, or a business executive. For a technical employee, we know his/her undergraduate degree major. For a marketing employee, we know the revenue generated by this employee to date. For a business executive, we know the number of years of experience.

Model the above using ER, translate the ER schema to SQL DDL. Your turn-in should include the ER schema, the SQL statements.