That's our margin of error. And we see out of all of these choices here, if we round to the nearest tenth, that'd be 28.9. So this is approximately 28.9, which is this choice right over here. This was an awfully close one, I guess they're trying to make sure that we're looking at enough digits. So there we have it. We have established our 95% confidence interval. Now one thing that we should keep in mind is, is this a valid confidence interval?