Requirements:

Airlines offer various flights.

Reservations for a flight can be opened or closed, and it is managed by the airline company.

A customer can make one or more reservations for different individuals.

A reservation is related to a single flight and a single passenger.

A reservation can be canceled or confirmed.

A flight has a departure airport and an arrival airport.

A flight has a departure date and time and an arrival date and time.

There may be stopover $($transfer$)$ airports on a flight.

The stopover $($transfer$)$ has arrival and departure dates and times.

Every airport serves one or more cities.

a$.$ Draw a class diagram.

b$.$ Define at least one use case for each component.

c$.$ Draw a sequence diagram for reservation process.

d$.$ Define a single process and draw an interaction diagram for your project.

e$.$ Provide two design pattern usage and a pseudo code for your design.