If a population has a high proportion of young people, the crude death rate may be low even if age-specific rates are high. This is an example of: MCQ with Answer and Explanation

Explanation:
An event with probability zero cannot occur under the given probability model, defining it as impossible (though in continuous distributions, point events have P=0 but are not impossible).

Explanation:
Σ(x - x̄) = 0 is a fundamental property of the arithmetic mean.

Explanation:
l₀ is the initial number of individuals in the life table cohort.