how we make the calculations by hand ? not using excel , i want to know what formulas must be used to compute them with the answers , thank you

Assume the following inputs: The annual rate of return on the S&P 500 over the past 75 years has average about 13.5% the US Treasury Bill rate. The standard deviation for the S&P 500 has been about 20% per year Assume that the future expectation for the US T-Bill rate is 5.0% Calculate the expected return, variance and standard deviation for portfolios that have the invested in T-Bills and the S&P 500 with weights as follows