2. Eddy and Harrison play a game as follows. Eddy selects a real number 9 at random and writes it down on a piece of paper. Harrison can ask Eddy what 9 is. Each time Harrison asks, Eddy tosses a biased coin secretly and tells Harrison the number 6 k if a head comes up (with probability p = 0.3) and the number 9 + k if a tail comes up (with probability 1 p = 0.7) for some k > 0. Harrison knows the values of p and k, and has to estimate the true value of 6 after asking Eddy twice based on the numbers X1 and X2. (a) Dene Y = (X 1 + X2)/ 2. Construct an unbiased estimator of 6, namely T, based on Y. (b) Dene W _ Y, for X1 # X2, _ X1 +a, for X1 2 X2. Find the value of a such that W is an unbiased estimator of 0. (c) Intuitively, which estimator do you think is a better estimator, T or W