8.4 Coca-Cola and demographics. Refer to Exercise 8.2 (page 485).

1. (a) Find , the standard error of .

2. (b) Give the 95% confidence interval for p in the form of estimate plus or minus the margin of error.

3. (c) Give the confidence interval as an interval of percents.

4. (d) State your conclusion and interpret the meaning of the confidence interval in part (c).