**FRIDAY PUZZLE 28th May 2010**

You're standing next to 3 light switches.

The switches belong to 3 bulbs in an upstairs room behind a door – the door is shut tightly & heavy, which means that it’s absolutely impossible to see if any bulb is on or not.

All 3 switches are now in the off position.

You can do whatever you want with the switches and when you're finished you open the door and go into the room.

While in there you are able to tell which switch belongs to which bulb.    How is this so?