You are to conceptualize the design of a web app for managing mobile carrier subscription, which includes billing and plan management usage history, both from the consumer and administrator side.

Draw a use case diagram (this should include at least 7 use cases).

Draw a class diagram. Be sure to use the appropriate graphical notation for each relationship type. Each class definition should include the main attributes and methods.

Draw a sequence diagram for making a bill payment. The customer may use different payment methods (e.g. paypal, credit card)