1.X~N(a, b) normal distribution, E(X)=a, d (x) = b. 2, X~U(a, b) uniform distribution, E(X)=(a+b)/2, d (x) = 3. The binomial distribution of x ~ b (n, p) refers to E(X)=np and D(X)=np( 1-p). 4.x obeys the exponential distribution with parameter λ, then E (x) = 1/λ, and D (x) = 1/λ 2. 5. If x obeys Poisson distribution with parameter λ, then E(X)=D(X)=λ. 6.X obeys the 0- 1 distribution with the parameter p, then E(X)=p and D(X)=p( 1-p). 7.X obeys the geometric distribution with parameter p, then E(X)= 1/p, and D (x) = (1-p)/p 2.