Let y1 and y2 denote the number of times that persons a and b toss the coin, respectively. if heads occurs with probability p and tails occurs with probability 1−p, it is reasonable to conclude that y1 and y2 are independent and that each has a geometric distribution with parameter p. consider y1−y2, the difference in the number of tosses required by the two individuals.

find v[y1y2].