The return on stock Ais 13 if the economy is good and if the economy is bad. The return on stock Bis.09 if the economy is good and os if it is bad. The probability of a good economy is sox and the probability of a bad economy is also 50%. Find the standard deviation for a portfolio invested 75% in A and 25% in B. 0.04 0.05 0.06 0.07 2 pts