The Performance Fund had returns of 19% over the evaluation period and the benchmark portfolio yielded a return of 17% over the same period. Over the evaluation period, the standard deviation of returns from the Fund was 23% and the standard deviation of returns from the benchmark portfolio was 21%. Assuming a risk-free rate of return of 8%, which one of the following is the calculation of the Sharpe index of performance for the Performance Fund over the evaluation period? 0.3913. 0.4286. 0.4783. 0.5238