osAu-pze : -P k=1 —-E(Xk)≥ =收.-产)≤是% n 故 m倍2c小=0       ≤ − p ≥ ε n n P A 0 故 lim  = 0      − ≥ →∞ p ε n n P A n = ( − ( ) ≥ ε ) P Y n E Y n n pq ≤ ⋅ 2 1 ε             = − ≥ ∑= ( ) ε 1 k n k k E X n X P