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Answer: Handwashing. It is estimated that washing hands with soap and water could reduce diarrheal disease-associated deaths by up to 50% 1. Researchers in London estimate that if everyone routinely washed their hands, a million deaths a year could be prevented 2.
Explanation:
ΔH2 = - δH1 δH2 = - 2 x δH1 δH2 = 2 x <span>δ</span>H1
