Trivia Thread

[Paradox313]

Saw it on a different forum, thought it might be nice here.

Anyways, rules:

* You may ask pretty much any trivia questions. I prefer history based questions
* Please quote the question you're answering
* After someone correctly answers you question, edit your question-post with something like "correctly answered by:" So people wont answer questions already answered
* Use of Google IS allowed
* This is not a turn-based thread (thus you need to quote the question)

Ok, here's the first ones:

1) Why was margarine developed?
2) What's the full version of the abbreviation AK?
3) What is the "Russian" acronym for the RPG anti-tank weapon? correctly answered by pb34
4) What is a supernova? - Correctly Answered by, tater_salad