About use case diagrams
Overview
Use case diagrams display relationships between use cases and actors in the system.
Tip: To make more space available to view your artifact(s), you can collapse both the utility panel and the explorer panel by clicking the full screen button 
(the lower rightmost corner of the window).
Use Case Diagram Artifact Properties
By default,
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Name: Indicates the name of the use case diagram.
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Id: Provides a unique identifier for the use case diagram. The Id cannot be modified.
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Type: Indicates the type of artifact.
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Width: Indicates the width of the use case diagram, measured in pixels. The maximum size is 7000 pixels.
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Height: Indicates the height of the use case diagram, measured in pixels. The maximum size is 7000 pixels.
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Show Conditions: Indicates whether or not conditions are shown.
Your instance administrator can
