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• San Juan Sailboat Charters is an agent that
  leases sailboats to customers for a fee. The
  boats are not owned by San Juan, but rather
  leased from boat owners who wish to earn some
  income when they are not using their boats. San
  Juan specializes in boats that can be used for
  multi-day or weekly charters, their size varying
  between 28 and 51.
• Each sailboat is fully equipped at the time it is
  leased. Most of the equipment is provided by the
  owners, but some is added by San Juan. The
  owner-provided equipment includes what is fixed
  on the boat (e.g., radios), and San Juan provides
  consumable equipment (e.g., toilet paper).
  Customers are responsible for the equipment on
  the boat during the period of their charter.
• All the equipment is tracked by San Juan San
  Juan likes to keep accurate records of its
  customers and their charters, including
  itineraries and weather conditions experienced
  during each trip.
• In some cases, the customers request services of
  crew members, and then San Juan hires such
  personnel on a part-time basis.
• Sailboats often need maintenance. All scheduled
  and unscheduled maintenance activities and costs
  are recorded and reported to the boat owners. If
  necessary, unscheduled repairs are performed by
  customer during a chapter, in coordination with
  the San Juan dispatcher.

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• The Jefferson Dance Club teaches social dancing
  and offers both private and group lessons.
  Jefferson charges 45 per hour per student for a
  private lesson and 6 per hour per student for a
  group lesson. Non-students can take lessons by
  paying the 50 additional fee. Private lessons
  are offered throughout the day, six days a week.
  All group lessons start at the same time (7pm).
• Jefferson employs two types of instructors
  full-time salaried instructors and part-time
  teachers. The full-time salaried instructors are
  paid a fixed amount per week, and the part-time
  instructors are paid a set amount for teaching a
  particular class, based on their individual
  hourly rate and the class duration. Sometimes,
  two teachers are involved in teaching the same
  private lesson.
• Jefferson would like to develop an information
  system to keep track of customers and the classes
  they are taking (including the schedule of their
  classes). Jeffersons management would also like
  to know how many and which types of lessons each
  teacher has taught and to be able to compute the
  bi-weekly payment of each teacher.

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