Bookmarks Prof c review. C Solved: Ecology: * Course Hero .com/cour s/35694/quizzes/158075/take Question 20 7.2 pts Do bonds reduce the overall risk of an investment portfolio? Let x be a random variable representing annual percent return for the Vanguard Total Stock Index (all Stocks). Let y be a random variable representing annual return for the Vanguard Balanced Index (60% stock and 40% bond). For the past several years assume the following data. Compute Zy 2- 15 10 38 31 26 27 -15 -15 27 18 25 18 18 -3 -24 2,551 2.451 6 2.460 2.535 2.560 Question 21 7.2 pts ZO OWP