Answer:
how many letters are there in the alphabet
Brown I am and much admired; many horses have I tried; tire a horse and worry a man; tell me this riddle if you can.
The one who makes it, sells it. The one who buys it, never uses it. The one that uses it never knows that he’s using it.
I'm white, I'm round, but not always around. Sometimes you see me, sometimes you don't.
I am whole but incomplete. I have no eyes, yet I see. You can see, and see right through me. My largest part is one fourth of what I once was.
I can only be played on a windy day