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In August and September 2005, Hurricanes Katrina and Rita caused extraordinary flooding in New Orleans, Louisiana. Many homes were severely damaged or destroyed; of those that survived, many required extensive cleaning. It was thought that cleaning flood-damaged homes might present a health hazard due to the large amounts of mold present in many of the homes. The article “Health Effects of Exposure to Water-Damaged New Orleans Homes Six Months After Hurricanes Katrina and Rita” (K. Cummings, J. Cox-Ganser, et al., American Journal of Public Health, 2008:869–875) reports that in a sample of 365 residents of Orleans Parish who had participated in the cleaning of one or more homes, 77 had experienced symptoms of wheezing, and in a sample of 179 residents who had not participated in cleaning, 23 reported wheezing symptoms (numbers read from a graph). Can you conclude that the frequency of wheezing symptoms is greater among those residents who participated in the cleaning of flood-damaged homes?
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