Please show the work as if it is done on paper! Thank you so much!

The covariance between Alphabet Inc's returns (Ticker: GOOG) and Diamondback Energy, Inc.'s (Ticker: FANG) returns is 0.004640878. Alphabet Inc. has a variance of returns of 0.0037628 while Diamondback Energy, Inc. has a variance of returns of 0.0282081. Alphabet Inc. has an average return of 2.109043 percent while Diamondback Energy, Inc. has an average return of 1.190338 percent. Calculate the standard deviation of returns for a portfolio consisting of 60 percent Alphabet Inc. stock and 40 percent Diamondback Energy, Inc. stock