What does Yahoo do with all our answers?

yeah,they keep it in some sort of giant database so that other users can search for information regarding some questions.that means,the database getting bigger and bigger each day.

must be like a graffiti-making man,spraying those sprays around for eternity.

It just stores all the answer so that people who has the same doubt in future may read it and get the solution! It's just like a social service!!!;-)

Like the old song says...

"They put 'em in a box, tie 'em with a ribbon, and throw them in the deep blue sea!"

did u take ur medication......
there are more imp things in life