有没有人能帮帮小弟 Q1:the mean of the probability distribution of the

有没有人能帮帮小弟 Q1:the mean of the probability distribution of the sample mean is A) A static B
Q1:the mean of the probability distribution of the sample mean is
A) A static B) a random variable C) a parameter D) always equal to sample mean
Q2:A sampling distribution is defined as the probability distribution
A) of possible sample sizes that can be observed from a given population
B) of the values of a statics based on samples of a given size from a given population.
C) Of a population parameter based on independent,random sampling of observations from the population distribution.
D) Of the values of a statistic based on different-sized samples taken from the population distribution.
Q3:For a normal population,an increase in sample size has an effect primarily on which property of the sampling distribution of the sample mean:
a) Dispersion b) Kurtosis C) skewness D) central tendency