The z-score formula is: $z = \frac{x - \mu}{\sigma}$, where $x$ is the value we're interested in, $\mu$ is the mean, and $\sigma$ is the standard deviation.
For 272 days, the z-score is: $z = \frac{272 - 266}{16} = \frac{6}{16} = 0.375$.
Now, we need to find
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