MSFT has an expected return of $0\mathrm{.}25$ and a standard deviation sigma of $0\mathrm{.}28$

WMT has an expected return of $0\mathrm{.}2$ and a standard deviation sigma of $0\mathrm{.}15$

The correlation between MSFT and WMT is $0\mathrm{.}54$

Compute the standard deviation of the portfolio if you invest a fraction $0\mathrm{.}75$ into MSFT and the rest into WMT$.$

Can you show me the process please