19. A random sample of size 36 is to be selected from a population that has a mean u = 50 and a standard deviation o of 9. 5pt. ea. (Must show your work). a. Find the mean of the sampling distribution. b. Find the standard error of this sampling distribution. c. What is the probability that the sample mean will be within 2 units of the mean. 20. Consider the approximately normal population of heights of male college students with mean u = 69 inches and standard deviation o = 4 inches. A random sample of 25 heights is obtained. 5pt. ea. (Must show your work). a. Describe the distribution of x, height of male college students. b. Find the proportion of male college students whose height is greater than 70 inches. c. Describe SDSM, the mean of samples of size 25. d. Find the mean and standard error of SDSM. e. Find P(x > 68) f. Find P(x