The historical stock returns for TechFluent, Inc. are shown below: Return 12% Year 1 2 -6% 3 22% 0% 4 What is the standard deviation of returns for TechFluent, Inc. stock over this 4-year period. (Compute the standard deviation assuming this is a population of returns, not a sample - that is, use the procedure described in the textbook for calculating the standard deviation of a series of stock returns). Record your answer as a percent, rounded to two decimal places, but do not include a percent sign in your answer. For example, enter 0.1571658 = 15.71658% as 15.7