There are 2,000 eligible voters in a precinct. a total of 500 voters are randomly selected and asked whether they plan to vote for the democratic incumbent or the republican challenger. of the 500 surveyed, 350 said they would vote for the democratic incumbent. using the 99% level of confidence, what are the confidence limits for the proportion that plan to vote for the democratic incumbent? ( use student's t distribution (appendix b.5) at infinite degrees of freedom for three decimal accuracy of the required z value.)