Q1: Each GROUP-LESSON consists-of zero or many CUSTOMERs and each
    CUSTOMER may be in zero or more GROUP-LESSON's
    Each CUSTOMER takes zero or more PRIVATE-LESSON's and each
    PRIVATE-LESSON may have one or two CUSTOMER's
    Each TEACHER teaches zero or more PRIVATE-LESSON's and each
    PRIVATE-LESSON is taught by one or two TEACHER's
    Each TEACHER leads zero or more GROUP-LESSON's and each
    GROUP-LESSON is led by one TEACHER 
    Each TEACHER attends one or more DANCE's and each DANCE is 
    attended by one or more TEACHER's
    TEACHER's are either FULL-TIME or PART-TIME but cannot be both.
    PRIVATE-LESSON's are dependent on CUSTOMER's

Q2: CUSTOMER (SSN, FirstName, LastName, Age, Street, City, State,
              Zip, Phone#)
    TEACHER(SSN, FirstName, LastName, Street, City, State,
             Zip, Phone#, DanceStyle, Title)
    FULL-TIME(SSN, TenureStatus, Salary) 
    PART-TIME(SSN, PayRate)
    DANCE(DanceID, Date, Time, DanceTitle, AdmissionFee)
    GROUP-LESSON(GroupID, Day, Time, DanceStyle, Fee, SSN)
    PRIVATE-LESSON(PrivateID, Day, Time, DanceStyle)
    consists-of(SSN, GroupID)
    teaches(SSN, PrivateID)
    attends(SSN, DanceID, Role)
    takes(SSN, PrivateID, Fee)

    Note: See how the weak entity PRIVATE-LESSON is handled. Since the
          relationship "takes" is many-to-many (2:N) we must implement
          this relationship as we would any other such relationship and
          so we override the requirement for PRIVATE-LESSON to contain 
          the primary key of CUSTOMER as a foreign key.

    Note: This is a more complex scenario than you will see in Q5 or the 
          Final. Relationships between weak entities and other entities 
          can be expected to be 1:N.