George has $60,000 invested in Goldman Sachs stock and $80,000 invested in Apple stock. He has calculated that the variance of 1-year Goldman Sachs returns is 0.034596 and the variance for Apple is 0.018496. He has calculated the covariance between the two stock returns as 0.0068. What is the standard deviation of the 1-year returns for his portfolio? Round your answer to the nearest cent (two decimal places).