In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

Q: Question: A flu vaccine was administered to residents in a large city and the vaccine was effective in lowering the risk of flu among the residents. This means that the lower risk of disease resulted in a 
 Answer: lower death rate.

A: With better food and less chance of disease, the death rate fell.
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Q: Question: Exponential growth of a population of animals means it 
 Answer: increases

A: With exponential growth, the population starts out growing slowly. As population size increases, the growth rate also increases.
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Q: Question: The Moon has _____ effect on the tides than Mars. 
 Answer: more

A:
The Moon has a greater effect on the tides because, although it is much smaller than the Sun, it is much closer.
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