Recently, ACT, Inc. reported that 71.9% (363) of 505 randomly selected college students in public colleges that were freshmen in 2010 returned to college in 2011 for their sophomore year. a) Estimate...

Recently, ACT, Inc. reported that 71.9% (363) of 505 randomly selected college students in public colleges that were freshmen in 2010 returned to college in 2011 for their sophomore year.

a) Estimate the national freshman-to-sophomore retention rate in colleges with a public 95% confidence interval.

b) Choose the correct answer to the following statement: If we calculated a 98% confidence interval instead of 95% confidence interval, the 98% confidence interval would be:

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c) Choose the correct interpretation of the 95% confidence interval in part a:

1. In 95% of all random samples of public colleges, the freshman-to-sophomore retention rate will be 71.9%.


2. In 95% of all random samples of public colleges, the freshman-to-sophomore retention rate is between 68.0% and 75.8%.


3. There is a 95% chance that the interval (68.0%, 75.8%) contains the true freshman-sophomore retention rate for public colleges.


4. There is 95% confidence that the true freshman-to-sophomore retention rate of public colleges is in the interval (68.0%, 75.8%)


5. If many random samples are selected, each sample with 505 public college freshmen, 95% of the sample freshman-to-sophomore retention rates will be in the interval s: (.680, .758).

1, 2, 3, 4 or 5: