The histoncal returns tor two investments - A and B-are summarzed in the following table for the period 2016 to 2020 . Use the data to answer the questions that follow 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 imvestment'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 less deviation from the average C. Investment A and investment B have equal risk because the average retums are the same D. The niskier investment appears to be investment B, with returns that are closet to the average relative to investment A, whose returns are farther from the average b. The standard deviation for investment A is