COMPUTER SCIENCE AND ENGINEERING
SOFTWARE ENGINEERING
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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source of input data only
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source of input data or destination of results
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destination of results only
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repository of data
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Detailed explanation-1: -An external entity, which are also known as terminators, sources, sinks, or actors, are an outside system or process that sends or receives data to and from the diagrammed system. They’re either the sources or destinations of information, so they’re usually placed on the diagram’s edges.
Detailed explanation-2: -RULE 4: An external entity is used to help determine the system boundary. They are external to the system being studied. They are often beyond the area of influence of the developer. RULE 5: An external entity can represent another system or subsystem.
Detailed explanation-3: -External Entity – Also known as actors, sources or sinks, and terminators, external entities produce and consume data that flows between the entity and the system being diagrammed. These data flows are the inputs and outputs of the DFD.
Detailed explanation-4: -A data store should be connected to at least one process. 4. External entities should not be connected to each other. Although they communicate independently, that communication is not part of the system we design using DFDs.