Approval 2011 In November 2011, Barack Obama’s approval rating stood at 45% in Rasmussen’s daily tracking poll of 1500 randomly surveyed U.S. adults.  a) Make a 95% confidence interval for his...

Approval 2011 In November 2011, Barack Obama’s approval rating stood at 45% in Rasmussen’s daily tracking poll of 1500 randomly surveyed U.S. adults.

 a) Make a 95% confidence interval for his approval rating by all U.S. adults.

 b) Based on the confidence interval, test the null hypothesis that Obama’s approval rating was no worse than his November 2009 approval rating of 50%.