Consider the two (excess return) index-model regression results for stocks A and B. The risk-free rate over the period was 8%, and the market's average return was 12%. Performance is measured using an index model regression on excess returns. a. Calculate the following statistics for each stock: (Round your answers to 4 decimal places.) b. Which stock is the best choice under the following circumstances? Consider the two (excess return) index-model regression results for stocks A and B. The risk-free rate over the period was 8%, and the market's average return was 12%. Performance is measured using an index model regression on excess returns. a. Calculate the following statistics for each stock: (Round your answers to 4 decimal places.) b. Which stock is the best choice under the following circumstances