1. (Are more data helpful?o) Suppose a stock's rate of return has annual mean and variance of-and 2. To estimate these quantities, we divide l year into n equal periods and record the return for each period. Let rn and .? be the mean and the variance for the rate of return for each period. Specifically, assume that r,-r and 2. Ifn and are the estimates of these, then r nrn and 2-no, . Let (F) and (82) be the standard deviations of these estimates. (a) Show that (r) is independent of n. (b) Show how (82) depends on n. (Assume the returns are normal random variables.) Answer the question posed as the title to this exercise 1. (Are more data helpful?o) Suppose a stock's rate of return has annual mean and variance of-and 2. To estimate these quantities, we divide l year into n equal periods and record the return for each period. Let rn and .? be the mean and the variance for the rate of return for each period. Specifically, assume that r,-r and 2. Ifn and are the estimates of these, then r nrn and 2-no, . Let (F) and (82) be the standard deviations of these estimates. (a) Show that (r) is independent of n. (b) Show how (82) depends on n. (Assume the returns are normal random variables.) Answer the question posed as the title to this exercise