Math Brain Twisters

I need this tornado of brain of maths in a manner that his expense, you will be curious to resolve it, and after knowing the response, you will realize that oh yes! that the response! ...

Haha, therefore do you look for some advertising mental campaign? pleasant.
I cannot give you a tornado of brain of maths, but a thought the brain tornado:

There is a boat, if you obtain over you drown but if you leave it you cross the river without accident. Which is this boat?
The sturdy and comical way takes you to the destination, but on the well lit road that you pillaged. Which way is that?
There is a house, if you sit in him soaked you, but if you remain outside it remain for you dry! !
Can you think about such a house?