(1)P(X2=1)=P(X2=1,X1=0)or(X2=1X1=1) =P(X2=11X1=0)P(x1=0)+P(X2=1X1=1)P(X1=1) =(0.3)(0.1)+(0.8)(0.9)=0.75 P(X2=0)=1-P(X2=1)=1-0.75=0.25 2)P(X3=0)=P(X2=0,X2=0)or(X2=0,X2=1) P(X3=0,x2=0)+P(X3=0,x2=1) P(X3=0X2=0)P(X2=0)+P(X3=0X2=1)P(X2=1) (0.7)(0.25)+(0.2)(0.75)=0.325 P(X3=1)=1-P(X3=0)=1-0.325=0675 (3)P(x,=0X2=0)=P(x2=0.X=0)=Px=0x2=0x2=0 P(X3=0) P(X2=0 (0.7)(0.25)_0.175 ≈0.538 0.3250.325 -2,for-∞<x<-2 号x-1,for-2≤x<0 2. Y=g(r)with 8(x)= x+1,for0≤x<2 for 2< (4)For-2<y≤-1,f(y) (a)2f2(2y+2)(b)2fx(2y-2)(c)f2(y+)(d)fxy-)(e)None2 (1) 2 2 1 2 1 P(X 1) P((X 1,X 0) or (X 1,X 1)) 2 1 1 2 1 1  P(X 1|X 0)P(X 0)P(X 1|X 1)P(X 1) (0.3)(0.1)(0.8)(0.9)0.75 2 2 P(X 0) 1P(X 1) 10.750.25 (2) 3 3 2 3 2 P(X 0) P((X 0,X 0) or (X 0,X 1)) 3 2 3 2  P(X 0,X 0) + P(X 0,X 1) 3 2 2 3 2 2  P(X 0|X 0)P(X 0)P(X 0|X 1)P(X 1) (0.7)(0.25)(0.2)(0.75)0.325 3 3 P(X 1) 1P(X 0) 10.3250.675 (3) 2 3 3 2 2 2 3 3 3 ( 0, 0) ( 0| 0) ( 0) 0| 0 ( 0) ( 0) ( ) P X X P X X P X X P X P X P X            (0.7) (0.25) 0.175 0.538 0.325 0.325     2. Y  g(X ) with 1 2 1 2 2, 1, 1, 2, ( ) x g x x          for 2 for 2 0 for 0 2 for 2 x x x x              . Then, (4) For 2  y  1, ( ) Y f y ____ ? (a) 2 (2 2) X f y (b) 2 (2 2) X f y (c) 1 2 ( 1) X f y (d) 1 2 ( 1) X f y (e) None