The characteristic function of Poisson distribution is

The skewness in a binomial distribution will be zero, if

An experiment succeeds twice as often as it fails. The chance that in the next six trials, there shall be atleast four successes is

A probability distribution in which mean is equal to variance is

The mean and variance of a binomial distribution are 8 and 4 respectively. Then P(X=1) is equal to

The height of persons in a country is a random variable of the type