What the zookeeper can try to do is, well they take a sample and in this case, they took a sample of 30 days and they calculated a sample statistic, in this case the sample mean of 350 kilograms. I don't know if it's actually to the right of the true parameter but just for visualization purposes, let's say it is. So let's say sample mean and this is their first sample. It was 350 kilograms and then using this, using the sample, they were able to construct a confidence interval from 341 to 359 kilograms and so the confidence interval, I'll draw it like this. We actually aren't sure if it actually overlaps with the true mean like I'm drawing here but just for the sake of visualization purposes, let's say that this one happened to. The whole point of a 90% confidence level is if I kept doing this, so this is our first sample and the associated interval with that first sample and then if I did another sample, let's say this is the mean of that next sample so that's sample mean two and I have an associated confidence interval and that interval, not only the start and end points will change but the actual width of the interval might change depending on what my sample looks like. What a 90% confidence level means that if I keep doing this, that 90% of my confidence intervals should overlap with the true parameter, with the true population mean.