You run a coaching/tutoring service to help high school students prepare for the SAT.  You have a staff of tutors, each of which has an hourly rate (such as $20 per hour) and personal information consisting of first name, last name, middle name/initial, street address, city, state code, zip code, phone number, mobile phone number, and e-mail address.  For each high school student, you want to keep similar personal information, date of birth, and expected date of graduation from high school.  Tutoring takes place in sessions, each consisting of one tutor and one student.  In addition to being able to identify the tutor and student involved in each session, you want to store its start time and end time.   

Design a database to hold this information.  Assume you do not have access to a zip code table.