According to a recent survey, the population distribution of number of years of education for self-employed individuals in a certain region has a mean of 14.4 and a standard deviation of 4.0. a. identify the random variable x whose distribution is described here. b. find the mean and the standard error of the sampling distribution of x overbar for a random sample of size 64. interpret them. c. repeat (b) for nequals256. describe the effect of increasing n.