11. The mean weight of items coming from a production line is 83 pounds. On the average, 19 out of 20 of these individual weights are between 81 and 85 pounds. The average weights of six randomly selected items are plotted. What proportion of these points will fall between the limits 82 and 84 pounds? What is the precise nature of the random sampling hypothesis that you need to adopt to answer this question? Consider how it might be violated and what the effect of such a violation might be on your answer.