Answer to Question 1
Black-box modeling, in the context of components, represents a component as a simple icon or a box that specifies its interface(s) without exposing its internal structure. White-box modeling, in the context of components, reveals the internal structure of a component. In black-box modeling, we represent the interfaces that the component supports as lines that end in a circle. The outside world can interact with the component only through these interfaces. In turn, if the component requires an external interface in its environment, the requirement is shown as a line ending in a half-circle. In white-box modeling, the internal structure of the component is shown as a diagram inside the stereotyped box that represents the component. The communication between entities inside the box and outside entities takes place through ports, shown as small boxes that are situated on the borders of the component box. An incoming port delegates a provided interface to an object, or another component, inside the component. An outgoing port conveys requests by internal entities to the required interface of an outside component.
Answer to Question 2
B
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