You turn on one switch and leave it on for a while. You then turn that one off and turn on another. Then - enter the room. You go to see if a bulb is warm, if its is - then its the first. If a bulb is on, then its obviously the second and if neither of those, its the switch you didnt use. It makes sense in my head - dont know if I'm right though :)I expect you'll find this easy, but its all I can think of...Jane's mother has three daughters. One is called April, another May - what is the name of the third daughter?