AVANTIVE Corporation has five departments: administration, marketing, sales, shipping, and purchasing. Each department employs many employees. Each employee has an ID, a name, a home address, a home phone number, and a salary and tax ID (Social Security number). Some employees are classified as sales representatives, some as technical support, and some as administrators. Sales representatives receive a commission based on sales. Technical support employees are required to be certified in their areas of expertise. For example, some are certified as drivetrain specialists; others, as electrical systems specialists. All administrators have a title and a bonus. Given that information, create the ERD containing all primary keys, foreign keys, and main attributes.