申論題

4. [10%] An online poll states that 50% people dislike a certain policy. For the next poll on the same topic, let be the point estimate of the true proportion ±2.5%? (Note:is the cumulative distribution function of a standard normal random variable Z. And 1.96² = 3.8416, 1.64² =2.6896, 1.28² =1.6384.)