Q2

Q: Identify what is being talked about here:
"One theory claims that its usage came about during the printing of the appendix of Rene Descartes' classic treatise "La Geometrie". While the text was being typeset the printer ran short of certain letters in the alphabet and therefore used a single alternative for all of them."

Clues:
"La Geometrie" tells us it has something to do with (that most hated of things) Mathematics.(wince!).
Rene Descartes confirms that, but you don't need to know he was a mathematician.
"The printer ran short of certain letters in the alphabet" mean that this has something to do with the alphabet. Considering there was a printer involved, reasonable to assume that this is the Latin alphabet (English language).
"used a single alternative" Okay, we're clearly talking about a single letter of the alphabet here. One that was used often in this book that we know nothing about. But, importantly, that led to other people using it a lot. Now, we can make a reasonable guess. What's a 'often used letter in maths'?

If you guessed 'x', then you'd be right!
A: x

Must know:
1. The English alphabet.
Seriously, this is a pathetic minimum requirement if you want to quiz in English. If you don't know the English alphabet, please work out your priorities first.

2. Basic algebra.
Are you smarter than a fifth... I'll show myself out.

Would help:
Probably knowing Rene Descartes was a mathematician helps slightly, but you really don't need that.

And that's it. That was a very easy question to answer, made difficult just by the way it was asked. As long as you pick the right clues out, you should get to the answer for most questions.