how do I solve this in Excel? Please show what you enter in excel formula bar.

Relationship between the market risk premium, the T-bill rate, and the expected return on the market portfolio If Treasury bills are yielding 3.8% at a time when the market risk premium 5.6% the market portfolio should have what yield? then Market yields Calculating the beta of a portfolio that mixes the risk-free asset and the market portfolio, using the security market line (SML) 6.2% What is the beta of a portfolio with an expected return 10.5% if the T-bill yield is and the market risk premium is 8.3% T-bill rate= 6.2% Market risk premium= 8.3% E(Rp)= 10.5% Portfolio beta