Answer:
There is no control group and variables were not addressed.
Explanation:
In the context, it is given that there is a dumping ground in a small town called Love Canal and harmful chemical waste of industries are dumped there. Lately, it is noticed that there were traces of the toxic substances on the walls of the schools and the hospitals. The hospitals also noticed that during the period of 1970 to 1980, there were increase in the number of the birth defects in the area. The people of the Love Canal has genetic abnormalities and the chemical waste is responsible for it.
Thus it can be concluded that there is a no such any control group in this case. The confounding variables like the comorbidities as well as the family history of the genetic defects were not addressed.
The high heat capacity of water prevents fish body temperatures from changing during the winter.
