the Lusitania was sunk by what?
Well.. that's up for debate..
She was hit by a torpedo. Shortly after that, a second explosion occured.That second explosion caused her to sink.
The torpedo is believed to have either set off some of the ammunition that she was carrying, or to have set of a cole dust explosion when it hit one of the coalbunkers, or to have caused an explosion in the steam generating plant. The last one is the most plausible, according to the most recent research.
Indirectly though, it was still the torpedo that caused that second explosion. And without the second explosion, she would have probably sunk too
But anyway, it wasn't your turn.. As you know.. hehe
Regards,
Fred