Work it out......

You've probably heard this one before, but it always strikes me as being a pleasingly neat logical problem - you wake up to find yourself in a room with two doors. Also in the room are two robots. A voice through a loudspeaker tells you that one of the robots has been programmed to always tell the truth, and the other one to always lie. The voice also tells you that one door leads to freedom, and the other to certain death. You are allowed to ask one of the robots just one question, and then you must choose which door you are going to go through. You don't know which robot has been programmed which way, but in fact one question will be enough to identify the door to freedom. But what question, and which robot do you ask it of? Answer tomorrow.