How to draw & explain a use case diagram for a webservice comparing prices of electronic good i.e. laptop, desktop compuers, TV, dvd player etc.

Introduction to  UML 2 Use Case Diagrams (http://www.agilemodeling.com/artifacts/useCaseDiagram.htm)

Introduction to  UML 2 Use Case Diagrams (http://www.agilemodeling.com/artifacts/useCaseDiagram.htm)

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