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02 (20 points) Performance of stock screeners. Stock screeners are automated tools used by investment companies to help clients select a portfolio of stocks to invest in. The table below lists the annualized percentage return on investment (as compared to the Standard & Poor's 500 Index) for 13 randomly selected stock screeners provided by the American Association of Individual Investors (AAII). 9.0 .1 1.614.616.0 7.7 19.9 9.8 3.2 24.817.610.7 9.1 a. Find a 90% confidence interval for the average annualized percentage return on investment of all stock screeners provided by AAII b. Find a 99% confidence interval for the average annualized percentage return on investment of all stock screeners provided by AAII