To calculate the z-score for a given data point, you can use the formula:
\[ z = \frac{(X - \mu)}{\sigma} \]
where:
- \( X \) is the data point,
- \( \mu \) is the mean, and
- \( \sigma \) is the standard deviation.
Given:
- \( X = 82 \)
- \( \mu = 79 \)
- \( \sigma = 2.1 \)
Now, substituting the values into the formula:
\[ z = \frac{(82 - 79)}{2.1} = \frac{3}{2.1} \approx 1.4286 \]
Rounding this value to two decimal places, we get:
\[ z \approx 1.43 \]
Therefore, the correct answer is 1.43.