The historical returns for two investments- A and B-are summarized in the following table for the period 2013 to 2017 . Use the data to answer the questions that follow. \begin{tabular}{l|l} CHAPTER 4 & RETURN AND RISK \end{tabular} 153 a. On the basis of a review of the return data, which investment appears to be more risky? Why? b. Calculate the standard deviation for each investment's returns. c. On the basis of your calculations in part b, which investment is more risky? Compare this conclusion to your observation in part a