RentABoat Charters is an agent that leases sailboats to customers for a fee. RentABoat does notown any sailboats but instead leases them on behalf of boat owners who wish to earn income whenthey are not using their boats. Now, you are hired by RentABoat to design their lease managementsystem. Consider the following data requirements: Owner data include the name, address and the boats he/she owns. Owner names are unique and each owner could own one or more boats.
Each sailboat is identified by a registration number, and is owned by a unique owner. Other data on each boat include its length, type, and the fee charged by the owner for lease.
Each sailboat is fully equipped at the time it is leased. The equipments attached to the boat, such as compasses, depth indicators, stoves and refrigerators, are provided by the owners. The consumable equipments, such as soaps, towels and toilet paper, are provided by RentABoat and the quantity varies with individual lease. An important part of RentABoat responsibilities is to keep track of the equipments on the boat. Each equipment has a unique code, a type and a detailed description. For each owner-provided equipment, the boat that the equipment is attached to is recorded. For each RentABoat-provided equipment, the quantity of equipment that each lease provides is recorded.
Each lease is identified by a unique number and involves a boat, a customer, a deposit, a fee charged by RentABoat and an itinerary. When a customer rents a boat, his/her name and address are recorded. Customer names are assumed to be unique. The itinerary is uniquely identified by an id and has a date, duration and a textual description.
Most of RentABoat's business is bare-boat chartering, which means that no crew is provided. In some cases, however, customers request the services of crew members in the lease, and so RentABoat hires such personnel on a part-time basis. Each part-time crew member is assigned with a unique id. Other data include name, telephone, and expertise.

Required:
a. State clearly in your design, if any, key attributes, existence constraints, cardinality constraints (you can either the ratio and single/ double-line notation or (min, max) notation) or other constraints that are meaningful to the application.
b. State and explain any additional assumptions that are necessary and essential in your design.
c. Naming conventions: (1) Use singular names for entity types, rather than plural ones. (2) Entity type and relationship type names are in uppercase letters. (3) Attribute names have their initial letter capitalized.