Answer:
The incidence of the flu decreased by the end of the second week.
Explanation:
At the beginning of the first week, there were 12 people who contracted influenza and decreased to 3 by the second week.
The lungs hold air that is breathed in. Oxygen gas in the air moves into the blood. The heart pumps to transports this oxygenated blood to cells in the body that need it to produce energy. Hope This Helps! :)<span>
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