A stock has annual returns of 13 percent, 21 percent, -12 percent, 7 percent, and -6 percent for the past five years. The arithmetic average of these returns is _____ percent while the geometric average return for the period is _____ percent. a. 4.60; 3.89 b. 4.60; 3.62 c. 3.62; 3.89 d. 3.89; 4.60 e. 3.89; 3.62