Problem 12-9 Calculating Returns and Variability [LO1] You've observed the following returns on Crash-n-Burn Computer's stock over the past five years: 12 percent, -12 percent, 19 percent, 24 percent, and 10 percent. a. What was the arithmetic average return on the company's stock over this five-year b-1. What was the variance of the company's returns over this period? (Do not round b-2. What was the standard deviation of the company's returns over this period? (Do not period? (Do not round intermediate calculations and enter your answer as a percent rounded to 1 decimal place, e.g., 32.1.) intermediate calculations and round your answer to 5 decimal places, e.g. 16161.) round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) a. Average return b-1. Variance b-2. Standard deviation