own a portfolio which is 30 percent invested in U.S. Treasury bills, 20 percent invested in Stock ith a beta of 1.20, 10 percent invested in stock B with a beta of 90, and the remainder is invested in stock C Stock C is as equally risky as the market. The risk-free rate of return is 4 percent and the expected urn on the market is 10 percent. What is the portfolio beta? 0.60 0.80 0.73 1.10 2.20