I remember taking an exam in Anthony Russell's history class. He was walking up and down the aisles when he stopped by my desk and looked down at my paper. He said, "You don't know the answer, do you?" I replied that I did not know the answer. He leaned down and whispered the answer in my ear. I wrote it down and susequently passed the exam. I don't remember the question, but after 50 years I still remember the answer, it was "The Lusitania".

I knew the name Lusitania and that it was a ship, but had forgotten everything else about it.  

But totally coincidentally, I was watching a YouTube video (not about this topic, but it mentioned it) that gives "the question to that answer" the day before you posted this story!  So if we're playing "Jeopardy".....

"I'll take 'World War I' for a thousand, Alex..."

And for "Lusitania," the answer is:

"What is the name of the ocean liner - carrying both 2000 passengers and war supplies for England from New York - that was sunk by a German submarine in 1915 - and which helped lead the United States to become involved in the War?"  

(The luxurious Lusitania sank in minutes and 1200 people died.  And even though the Germans had warned the ship not to sail and made threats to attack it, the scope of the incident galvanized world - and US - opinion against Germany, altho' the US didn't go all in until 1917.)

The event is still controversial and there are conspiracy theories about how it happened even today.  Many details are at:

http://en.wikipedia.org/wiki/RMS_Lusitania

So there you go. Another old circle squared.