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Which three are valid method signatures in an interface? private int getArea(); public float getVol(float x); public void main(String [] args); public static void main(String [] args); boolean setFlag(Boolean [] test);

1 and 2
2, 3 and 5
3, 4, and 5
2 and 4

Correct Answer: 2, 3 and 5

Explanation:

(2), (3), and (5). These are all valid interface method signatures.

(1), is incorrect because an interface method must be public; if it is not explicitly declared public it will be made public implicitly. (4) is incorrect because interface methods cannot be static.

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