I found this one easy, considering my knowledge of South America isn't as strong as other places. The first 10 questions are pretty easy. I got 19/20 which surprised me.
The only one I found hard was about the straits of magellan, not that cook made any sense, but I never heard of the other. And I'm against making guesses.
As the whole dam thing could of been guessed if you ever glanced at a map