Question 1: A statistician wants to estimate the mean height h (in meters) of a population, based on n independent samples X_1,X_2,...,X_n, chosen uniformly from the entire population. He uses the sample mean M_n = (X_1+X_2+...+X_n)/n as the estimate of h. It is also given that the standard deviation of the height of the population is 1 meter.