The formula for the z-score is:
\[ z = \frac{X - \mu}{\sigma} \]
where \( X \) is the test score, \( \mu \) is the mean, and \( \sigma \) is the standard deviation.
For the geography test:
\( X = 75 \), \( \mu = 73 \), \( \sigma = 5.5 \).
\[ z = \frac{75 -
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