Answer:
1.
Whether the Supreme Court should decide a case depends on its jurisdiction and whether the case presents a constitutional question that requires resolution. In some instances, other courts or branches of government may have jurisdiction to hear the case or provide a resolution.
2.
The President's executive privilege is not absolute and can be limited in certain circumstances, such as when it conflicts with the needs of criminal justice or national security.
3.
The Supreme Court ultimately decided that Nixon had to turn over the tapes to the prosecution, rejecting his claim of executive privilege. The Court held that the need for the tapes in the pursuit of criminal justice outweighed the President's interest in keeping them confidential.