Title: A cappella.
Question: Where is the Sweet Adelines HQ?

Title: 2008 Summer Olympics torch relay.
Question: Which Olympics did Nagano host?

Title: Alsace.
Question: When did the Habsburgs sell the Sundgau territory to France?

Title: Treaty.
Question:
What Supreme Court case ruled that a treaty provision that conflicts with the US Constitution is null and void under US law?