Suppose that we will take a random sample of size n from a population having mean , and standard deviation o. For each of the following situations, find the mean, variance, and standard deviation of the sampling distribution of the sample mean x : (a) u = 18, 0= 2, n= 22 (Round your answers of "o ; " and "a ; 2" to 4 decimal places.) OX 2 (b) u = 494, 0= 3, n= 125 (Round your answers of "o ; " and "o ; 2" 2" to 4 decimal places.) LIK OX* 2