The following table shows percentage of investments in energy securities (x) and tax efficiency (y) for 10 mutual fund portfolios. X y 3.1 3.2 3.7 4.3 4.0 5.5 6.7 7.4 98.1 94.7 92.0 89.8 87.5 85.0 82.0 77.8 72.1 a) Determine the least square regression equation for the data above. b) Plot the scatter diagram and the least square regression line on the same graph c) Describe the relationship between percentage of investments in energy securities and tax efficiency for mutual fund portfolios. d) What does the slope of the regression line represent in terms of percentage of investments in energy securities and tax efficiency for mutual fund portfolios? e) Predict the tax efficiency of a mutual fund portfolio with 5.0% of its investments in energy securities. (25 marks) 7.4 10.6 53.5