Actively managed funds find it difficult to consistently earn higher risk-adjusted returns than a broad stock market index. The difference in return between actively managed funds and passively managed index funds can be explained by which of the following?
I. Lower expense ratios at index funds.
II. Higher turnover rates at index funds.
III. Differences in returns in sectors of the market and the overall market return.

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Stocks a, b, and c are similar in some respects: each has an expected return of 10% and a standard deviation of 25%. stocks a and b have returns that are independent of one another; i.e., their correlation coefficient, r, equals zero. stocks a and c have returns that are negatively correlated with one another; i.e., r is less than 0. portfolio ab is a portfolio with half of its money invested in stock a and half in stock b. portfolio ac is a portfolio with half of its money invested in stock a and half invested in stock c. which of the following statements is correct? a. portfolio ab has a standard deviation that is greater than 25%.b. portfolio ac has an expected return that is less than 10%.c. portfolio ac has a standard deviation that is less than 25%.d. portfolio ab has a standard deviation that is equal to 25%.e. portfolio ac has an expected return that is greater than 25%.

Your own record of all your transactions. a. check register b. account statement