Problem 12.9 Calculating Returns and Variability (LO1) You've observed the following returns on Regina Computer's stock over the past five years: 19%,13%,16%,21%, and 10% 0. What was the arithmetic average return on Regina's stock over this five-year period? (Round the final answer to 1 decimal place.) Average return b-1. What was the variance of Regina's returns ovet this period? (Do not round intermediate colculations. Round the final answer to 5 decimal ploces.) Vorlance b-2. What wos the standard deviation of Regina s returns over this period? (Do not round intermediare calculations. Round the final enswer to 1 decimal pleceJ Standard devation