Problem 12-15 Arithmetic and Geometric Returns [LO1] A stock has had returns of 7 percent, 15 percent, 21 percent, 17 percent, 21 percent, and 9 percent over the last six years. What are the arithmetic and geometric average returns for the stock? (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.)