logical ques and techinal skills regarding family backgrounds situational bassed ques and puzzle question they will ask about that prepare well in hand. 2. Three Switches One Light Bulb Puzzle: One trip to attic, identify correct switch. Answer: Turn on switch 1, wait, turn it off, turn on switch 2. Go up. If bulb’s on → switch 2. If warm → switch 1. If cold → switch 3.