Answer:
Confidence interval = [ 0.4432, 0.4968]
Explanation:
Registered voters approved of the job Barack Obama was doing as president,
p = 47% = 0.47
Total sample size, n = 2,294
Confidence level = 99%
now,
confidence interval for the proportion of all registered voters who approved of the job Barack Obama was doing as president
= p ±

for 99% confidence level, z value is 2.58
= 0.47 ±

= 0.47 ± 0.0268
or
Confidence interval = [0.47 - 0.0268, 0.47 + 0.0268 ]
or
Confidence interval = [ 0.4432, 0.4968]