I need help on Part A. I dont know how many classes i need to create. Also, i dont know how to create a state diagram.

A small catering business has recently expanded, and has requested a new computer system be developed to help manage and track the increasing number of catering orders. A system analyst has met with representatives from the company and learned the following requirements concerning the project. The primary purpose of the new computer system will be to facilitate tracking orders for the company's catering services. The company also wants the system to preserve customer information when orders are placed, as ell as historical information concerning the orders placed by each of its customers over time. Finally, the system should be capable of interfacing with the catering company's existing accounting and billing software, to provide it the billing information for catering events once an event has been completed To support these functions, the system should keep track of customer information including name, address email contact, phone number, and the details for one or more credit cards the customer will use for payment. When a new booking is made, a catering company booking agent checks to see if it is an order from a new customer or a repeat customer. If the customer is new, the booking agent records the customer's details. If the order is from a repeat customer, the customer information will already be known to the system The catering company only accepts payment by credit card, so each customer will have at least one credit card on file. If desired, customers are allowed to have multiple credit cards on file. The details that are needed for credit cards that a customer plans to use for payment consist of an account holder name, a credit card type, a credit card number, and an expiration date. The catering company has a list of 10 preset food menu options that it can serve at an event. Each menu option has a name, a description, and a price associated with it. When an order is placed by a customer, a selection of one of the preset menu options is specified When an order is placed the catering company booking agent records the following information concerning the event: time and date, location, expected number of guests, and the selected preset menu option to be served at the event. Based on this information the booking agent calculates the cost of providing catering services for the event and relays the amount to the customer. The customer then specifies the credit card to bill for the catering services As stated above, the company plans to use the new system to keep track of all of its orders. To support this function it wishes to be able to query the system and produce a report that shows all orders that have been taken for events that occur within a specified time interval. This will enable workers to always know which catering events have been booked for a specific time period and to plan accordingly to ensure they have enough supplies and staff on hand to handle all upcoming events