Head for mensheights.txt is: Please answer using r and scanning the file 164.7 164.7 164.7 169.5 181.9 169.4 177.8 181.3 2. (5 points.) The file mensheights.txt contains data on the heights of a representative sample of 3658 U.S. adult men, in centimeters. We'll approximate the population distribution using a Normal( ,2) distribution. (a) Find the MLEs of the mean , the variance 2, and the standard deviation . (b) Find the MLE of the interquartile range (the third quartile minus the first quartile.) Also find the interquartile range of the raw data. Are these two answers close? (c) Find the MLE for the probability a random U.S. adult man is taller than 199cm. If this were the true probability, what is the expected number of adult men taller than 199cm in a sample of 3658 adult men? How many men in the raw data were taller than 199 cm ? (d) The Normal model fits the data well, but not perfectly. In order to create a better-fitting model, what additional data would you like to get?.