Tell which button will turn on which light bulb , divide cake into 8 pieces with three cut only
Sigiloso
turn on first switch for 5 minute then kill it then turn on second bulb and enter the room. touch bulb, if hot switch A , the bulb which is not hot marked as c, glowing one is b. first place a horizontal cut then put one piece on second then cut second cut(now have 4 piece) again place three piece on one piece and cut it third time you have 8 pieces