The annual returns, in percentages, on stocks A and B for three possible states of the economy are given in the table below.
Economy State Probability StockA StockB
Good 0.5 40 20
Average 0.3 20 40
Bad 0.2 10 8
If one invested in StockA, what would be the standard deviation of the percentage return?Place your answer, in percent rounded to 1 decimal place, in the blank.For example, a standard deviation of 10.39 percent would be reported as 10.4.Do not use a percent sign.