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    What
    are we doing now? (Current System) 
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    What
    do we want to do? (Proposed System) 
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    How
    is this going to work, exactly? (Use Cases) 
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    What
    do we need? (Requirements) 
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    How
    are we doing this? (Object Models & State 
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    Diagrams) 
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    Are
    we missing something? (Open issues) 
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