How smart are you?

are you a know it all or do you have a mental disabilty

1 2 plus 2 to
2 the square root of pi? (try doing it without a calculator otherwise it wont work)4dp
3 on the periodic table why is leads symbol Pb?
4 how many letters are in this sentence
5 "if i had a hi fi" is a what
6 a year 8 kid made this so i wouldnt get it wrong un less you younger than 13