In a Poisson distribution, the probability of zero successes is e^{-λ}. If λ=3, this probability is approximately: MCQ with Answer and Explanation

Explanation:
P(A∪B)=P(A)+P(B)-P(A∩B). To maximize P(B) given P(A∪B)=0.7 and P(A)=0.4, set P(A∩B)=P(A)=0.4 (i.e., A⊂B). Then 0.7=0.4+P(B)-0.4 => P(B)=0.7 max.

Explanation:
Direct standardization uses the study population's age-specific death rates applied to the standard population's age structure; thus, only the study population's age-specific rates are needed.

Explanation:
Population momentum is the built-in growth potential resulting from a young age structure, even if fertility drops to replacement level.