A portfolio is made up of Stocks A, B, C, and D in the proportion of 20%, 30%, 25%, and 25% respectively. The nondiversifiable risks of the stocks as measured by their betas are 0.4, 1.2, 2.5, and 1.75 for stock A, B, C, and D respectively. The expected returns of the stocks are 12%, 24%, 30%, and 28% respectively. Measure the beta of the portfolio.