smoke stacks and pollution

A doctor and a researcher want to test whether people living in a neighbourhood with more pollution (close to a steel mill) have more respiratory issues than people living in a neighbourhood with less pollution (far away from the steel mill). The doctor conducts a respiratory examination for the 20 participants in the high pollution area and 20 participants from the low pollution area, and gives the participants a score out of 10. The researcher analyses the data and finds that the participants in the high pollution group had more respiratory problems in comparison to participants in the low pollution group.

flowers in a field representing fresh air

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