A dying old man wants to see which one of his 3 sons is the smartest, so he gives $10 to each of them and orders his sons to buy something that can fill the entire room.
Son #1 buys a bag of flour, brings it to the old man and smacks the bag on the floor. The room is immediately filled up with flour.
Son #2 buys a can of propane, brings it to the old man and opens the valve inside the room. The room is soon filled up with propane.
son #3 buys a candle and a box of match. He brings the candle to the old man and fucking lights it up.