please show me the excell, how to

Intro You want to invest in either a stock or Treasury bills (the risk-free asset). The stock has an expected return of 12% and a standard deviation of returns of 32%. T-bills have a return of 2%. Part 1 If you invest 30% in the stock and 70% in T-bills, what is your expected return for the complete portfolio? Attempt 1/5 for 1 pts. 3+ decimals Submit Part 2 What is the standard deviation of returns for such a portfolio? Attempt 1/5 for 1 pts. 3+ decimals Submit