In a study of cell phone use and brain hemispheric dominance, an Internet survey was e-mailed to 5000 subjects randomly selected from an online group involved with ears. 717 surveys were returned. Construct a 90% confidence interval for the proportion of returned surveys.

In each case,

(a) Find the best point estimate of the population proportion p;

(b) Identify the value of the margin of error E;

(c) Construct the confidence interval;

(d) Write a statement that correctly interprets the confidence interval.