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Q) What are the similarities between an abstract class and interface?




A)
->Both can’t be instantiated. Means abstract and interface objects can’t be created only reference can be created for them.
->Both can have “0” or more abstract methods.
->generally both are useful only in the context of inheritance. So, they are actually servicing for their children only.
->if inheritance is not there the abstract class and interface is useless.
->the interface and abstract methods should not implement in sub class then that child class declare as abstract.

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