Help me : riddles

I have collected some interesting puzzles who can answer?

1.What can''t be used until it''s broken?
2.In the alphabet... Which letter is always trying to find reasons?
3.In the alphabet...Which letter is not me?
4.What is as big as a horse but doesn''t weigh anything?
5.What begins with T, ends with T and has T in it?
6.Do you know why birds fly to south in the winter?
7.Which room has no doors, no windows.
8.What is the longest word?
9.Why did the man throw a bucket of water out the window?
10.Why did the man throw the butter out the window?

1. eggs
2.The letter Y.
3. Home
5. The letter T.