An investor plans to invest 75% of her funds in the common stock of Gamma Industries and 25% in Epsilon Company. The expected return on Gamma is 12%, and the expected return on Epsilon is 16%. The standard deviation of returns for Gamma is 8% and for Epsilon is 12%. The correlation between the returns for Gamma and Epsilon is +0.8. Determine the standard deviation of returns for this investor's portfolio.

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