shift B M alt fn ctrl 4. Tell me, how, starting with a cavity with mirrors on each end and filled with atoms, a laser works. For full credit your answer must be in at least 3 sentences. 5. You find an old string of Christmas lights in the basement of your grandparents' house. You plug them in and find that the string isn't working. You start checking bulbs and by the time you get to replacing the 4th bulb, the string re-lights. Is this string wired in parallel or series? How do you know? Would the voltage across the last light in the string be the same, less, or more than the voltage across the first bulb? How do you know? The lights are wired as .... I knew this because ... The voltage across the last bulb in the string would be (the same, less, or more) than/as the voltage across the first bulb because