Youve observed the following returns on Pine Computers 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 companys stock over this five-year period? (Do not round intermed calculations and enter your answer as a percent rounded to 1 decimal place, e.g., 32.1.) b-1.What was the variance of the companys returns over this period? (Do not round intermediate calculations and round your answer to 5 decimal places, e.g., .16161.) b-2. What was the standard deviation of the companys returns over this period?