1. For each of the following equations prove whether the estimator is an unbiased estimator of the population mean. Recall that E[Yi]=u. a) Zln(Yin) b) (Y1+Yn2) c) Zln(Yin1) 2. Consider only the equations in problem 1 for which you found that the estimator is unbiased. Which of those has the lowest variance? To help you prove that, assume that Var(Y)=1 and that n=1000