When You Extend an Interface, You Must Implement All the Methods

question 36

Multiple Choice

When you extend an interface, you must implement all the methods defined in the interface. If you are interested in only one or two mouse events, you can extend the ________ class which implements the MouseListener interface, but does not require you to write all the functions in the interface.

• A) MouseAdapter
• B) MouseExtender
• C) MouseMotionAdapter
• D) MouseMotionExtender

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Definitions:

Opportunity Costs

The loss of potential gain from other alternatives when one alternative is chosen.

Carrying Costs

Expenses associated with holding inventory, including storage, insurance, and obsolescence costs, among others.

Net Present Value

Net Present Value (NPV) is a financial metric used to evaluate the profitability of an investment, calculating the difference between the present value of cash inflows and outflows over a period of time.

Variable Cost

Costs that vary directly with the level of production or service volume, such as raw materials and direct labor expenses.