961. The covariance of two independent random variable is ___________
A. 1
B. 0
C. – 1
D. Undefined

962. The weight of persons in a state is a ___________
A. Continuous random variable
B. Discrete random variable
C. Irregular random variable
D. Not a random variable

963. In random experiment, observations of random variable are classified as ___________
A. Events
B. Composition
C. Trials
D. Functions

964. The expectation of a random variable X (E(X)) can be written as _________
A.ddt[MX(t)](t=0)
B.ddx[MX(t)](t=0)
C.d2dt2[MX(t)](t=0)
D.d2dx2[MX(t)](t=0)

965. If the probability of hitting the target is 0.4, find mean and variance.
A. 0.4, 0.24
B. 0.6, 0.24
C. 0.4, 0.16
D. 0.6, 0.16

966. If the probability that a bomb dropped from a place will strike the target is 60% and if 10 bombs are dropped, find mean and variance?
A. 0.6, 0.24
B. 6, 2.4
C. 0.4, 0.16
D. 4, 1.6

967. If P(1) = P(3) in Poisson’s distribution, what is the mean?
A. 2–√
B. 3–√
C. 6–√
D. 7–√

968. What is the mean and variance for standard normal distribution?
A. Mean is 0 and variance is 1
B. Mean is 1 and variance is 0
C. Mean is 0 and variance is ∞
D. Mean is ∞ and variance is 0

969. Find λ in Poisson’s distribution if the probabilities of getting a head in biased coin toss as 34 and 6 coins are tossed.
A. 3.5
B. 4.5
C. 5.5
D. 6.6

970. If P(6) = λP(1) in Poisson’s distribution, what is the mean?(Approximate value)
A. 4
B. 6
C. 5
D. 7