991. The expectation of a random variable X(continuous or discrete) is given by _________
A. ∑xf(x), ∫xf(x)
B. ∑x2 f(x), ∫x2 f(x)
C. ∑f(x), ∫f(x)
D. ∑xf(x2), ∫xf(x2)

992. Mean of a random variable X is given by _________
A. E(X)
B. E(X2)
C. E(X2) – (E(X))2
D. (E(X))2

993. Find the expectation of a random variable X if f(x) = ke-x for x>0 and 0 otherwise.
A. 0
B. 1
C. 2
D. 3

996. What is moment generating function?
A.Mx(t) = E(etx)
B.Mx(t) = E(e-tx)
C.Mx(t) = E(e2tx)
D.Mx(t) = E(et)

998. E(X) = npq is for which distribution?
A. Bernoulli’s
B. Binomial
C. Poisson’s
D. Normal

999. E(X) = λ is for which distribution?
A. Bernoulli’s
B. Binomial
C. Poisson’s
D. Normal

1000. E(X) = μ and V(X) = σ2 is for which distribution?
A. Bernoulli’s
B. Binomial
C. Poisson’s
D. Normal

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