Consider an experiment in which a fair coin is tossed repeatedly. Let random variable X be the number of the toss when the first head occurs, and let y be the number of the toss when the first tail occurs. (For example, if the sequence begins HHHTHTT, then X = 1 and Y = 4.) 1. Find the joint PMF of X and Y. Be sure to consider which pairs of x, y values can or cannot occur. 2. Are X and Y independent?