1. The public works division selects a random sample of 250 households and measures the volume of water consumption for each household over the course of a week. In addition to the weekly consumption, the household's service zone and the number of individuals listed as residents will be recorded. Identify an individual, the population, the sample, and all variables measured in this study. Classify each variable as qualitative (Q), discrete (D), or continuous (C): individual population sample variable(s)