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Date 3/1/2020 4/1/2020 5/1/2020 6/1/2020 7/1/2020 8/1/2020 9/1/2020 10/1/2020 11/1/2020 12/1/2020 1/1/2021 2/1/2021 R (CAT) 0.29% 4.17% 5.30% 5.04% 7.90% 4.81% 5.30% 11.21% 4.86% 0.45% 8.47% 0.72% Average 4.88% 4. Based on the table above, what is the St. Dev. of CAT historical returns based on the table above? a. 3.17% b. 3.31% c. 4.88% d. 5.12% e. 6.15%