To complete the sentences, we need to calculate the total number of cities, the percentage of cities in the Sur zone, and the percentage of cities not in the Norte zone. Let's compute these values.

For the variable 'Zona', which is categorical and nominal, the most appropriate measure of central tendency is the mode. This is because the mode identifies the most frequently occurring category within the data, which is useful for understanding the most common zone among the cities studied.

To find the arithmetic mean and geometric mean of the temperatures, we'll calculate these values using the appropriate statistical functions.

To find the value below which half of the cities have their precipitation, we'll calculate the median. The median is a measure of central tendency that divides the data into two equal halves.

To find the 37th percentile of precipitation, we'll calculate this value which indicates that 37% of the data falls below this point. This helps in understanding the distribution of precipitation across the dataset.

Significance: This value indicates that 37% of the cities have annual precipitation amounts of 460.84 mm or less. It is a measure of distribution that helps to understand how precipitations are spread among the cities.

Interpretation: A CV greater than 0.1 generally indicates a high level of variability relative to the mean. In this case, the CV of 0.53 suggests that the mean precipitation is not very representative due to significant variability in the data.

Observation: The calculated confidence interval does not contain 95% of the data as expected, but only about 32.65%. This discrepancy suggests that the distribution of precipitation may not be normal or there could be other influencing factors.