study of cell phone use and brain hemispheric​ dominance, an Internet survey was​ e-mailed to 2482 subjects randomly selected from an online group involved with ears. 1095 surveys were returned. Construct a 90​% confidence interval for the proportion of returned surveys.   ***QUESTION** Identify the value of the margin of error E. E= ?

A recent article published by the Wall Street Journal said the Cincinnati airport had the most expensive airfares among the largest airports in the US. While they had some statistics to support this statement, a statistician decided to investigate further. A sample of 46 flights originating in Cincinnati was selected, and the round-trip airfare for each flight was recorded. The sample data is summarized in the StatCrunch output below:    With 98% confidence, we estimate the mean airfare for flights out of Cincinnati is between $ and $. (Round the limits of your interval to 4 decimal places.) The mean airfare nationwide was reported as $376 for a round-trip ticket. Does the interval found above support the claim that Cincinnati has airfares which are more expensive than other airports in the US? The interval does not support the claim because the entire interval is not above $376. We can't make this conclusion based on a confidence interval. The interval does not support this claim…

In a random sample of 230 men , 18 or older , 142 were married. Construct and explain a 90% confidence interval estimate of a true population proportion of married men 18 or older.

A Gallup poll of 1487 adults showed that 43% of the respondents have Facebook pages.  Construct a 95% confidence interval for the proportion of adults who have a Facebook page.