How to solve this?

Consider the following information on a portfolio of three stocks: State of Economy Stock A Stock B Stock C Rate of Return Rate of Return Rate of Return Probability of State of Economy .15 .53 .32 .04 Boom Normal Bust .12 .18 .34 .24 -.23 .48 .22 -.37 Required: (a) If your portfolio is invested 36 percent each in A and B and 28 percent in C, what is the portfolio's expected return, the variance, and the standard deviation? (Do not round intermediate calculations. Round your variance answer to 5 decimal places (e.g., 32.16161) and input your other answers as a percentage rounded to 2 decimal places (e.g., 32.16).) 1% Expected return Variance Standard deviation % (b) If the expected T-bill rate is 4.35 percent, what is the expected risk premium on the portfolio? (Do not round intermediate calculations. Enter your answer as a percentage rounded to 2 decimal places (e.g., 32.16).) Expected risk premium %