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Let X1, X2 ... ~ Exp(1). Define Tn = X, + 1. (a) [1] Derive the limiting distribution of Vn(In - 2). (b) [1] Derive the limiting distribution of Vn(Tn - 2)/(Xn). (c) [1] Derive the limiting distribution of n(sin(Tn) - sin(2))