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3. Let X1,..., Xn denote a random sample from the uniform distribution on the interval (0, 0). Define two estimators T1 = 2Xn, T2 = X(n). (a) Are Ti and T2 unbiased estimators of 0? Can you build another estimator which is unbiased? Justify. (b) Find the mean squared errors of T1 and T2. Suppose n large, which estimator is more efficient