1.Identify the guy
2.
A sitter for F1 enthusiasts, for everyone else, try googling:
X was a one of the best formula one racers of his time often winning most his races not because he was the fastest on the circuit but because he was the smartest. A year before he retired for good, he took a one year hiatus from the sport. Identify X

3.
connect this equation :x¹² = 2
to the world of music.

4.Joanna Rowling claims that she had initially decided to keep X and Y alive but then had to finish them off so as to compensate for the revival of Arthur Weasley. Very vague Hint: Theodore Roosevelt's contribution to the world apart from Politics

Answer time:
1.Ho Chi Minh (Aravind, I told you it was a tribute question :P)
2.Alain Prost (Brilliant Answer Abhimanyu)
3.Frets (Nice one roshan)
4.Lupin and Tonks (Theodore gives Teddy, who is their son)