1. To construct a confidence interval for a single proportion using the Normal Distribution, we start with the [ Select ] ["p-value", "point estimate", "z*", "margin of error", "standard error"] , or the midpoint.
2. Then we add and subtract the [ Select ] ["z*", "margin of error", "point estimate", "standard error", "p-value"] from that number.
3. If we want a narrower confidence interval, we can either [ Select ] ["increase the sample size", "decrease the sample size"] or [ Select ] ["decrease the level of confidence", "increase the level of confidence."] .