EXERCISE 8 Answer the following questions: a. Consider the body fat data (see handout "Introduction to R"). We use here the variables y, x6, X9, X10. The variance covariance matrix and the sample means of the four variables are shown next: #Variance covariance matrix: y x6 x9 x10 y 70. 036 9.980 37. 483 24.587 x6 9. 980 5. 909 12. 799 8.879 x9 37.483 12.799 51 .324 33.715 x10 24. 587 8.879 33.715 27.562 #Sample means: y x6 x9 x10 19. 151 37.992 99.905 59. 406 Answer the following questions: a. Find the fitted line of the regression of y on 29. Show all your work. b. Compute the correlation coefficient between y and x10. c. Consider the regression of y on x6. Compute the value of the regression sum of squares