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2. Let X], X2, ..., Xn ~ Poisson (A). Show that the following are consistent estimators of A: (a) Xn. (b) S2. (c) axn + (1 - a)S,, for any a E [0, 1]. (d) m" Xn + 72. (e) E- 2 Xn. (f) sin _ . >- Xn ten. (g) Er-(Sn/i)? + also for any a, be R