Why are we not sick all of the time?

Please help this is due today and I really need help.

Our Immune system helps fight all the bacteria and viruses that could get us sick

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation:

the correct answer is: " ventricles " .

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