You've observed the following returns on Yamauchi Corporation's stock over the past five years: 28.8 percent. 16.2 percent, 35.4 percent, 3.6 percent, and 22.6 percent. a. What was the arithmetic average return on the stock over this five-year period? (Do not round Intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g. 32.16.) b. What was the variance of the returns over this period? (Do not found Intermediate calculations and round your answer to 6 decimal places, e.g. 32.161616.) c. What was the standard deviation of the returns over this period? (Do not round Intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g. 32.16.) a. Arithmetic average return b. Variance c. Standard deviation