If Yule's coefficient Q = 0 for attributes A and B, this indicates: MCQ with Answer and Explanation

Explanation:
Civil registration systems continuously record vital events (births, deaths, marriages) at the local level, providing the most timely and comprehensive source for vital statistics when well-functioning.

Explanation:
Sum initially = 9 × 12 = 108. After removing 15, sum = 93, n = 8. New mean = 93/8 = 11.625.

Explanation:
With 6 observations (even), median = average of 3rd and 4th values in ordered list: (20 + 25)/2 = 22.5. This splits the data into two equal halves.