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.
Ecosystems, the interactive system of living and nonliving organisms in a specific location, CHANGE SLOWLY OVER TIME. When new plants and animals arrive in an area, they either thrive or struggle. Thriving species sometimes displace native species. When this happens, the system as a whole begins to change.
I’m guessing false because the water cycle contains all water on earth I think
Decrease in the tree population can damage the environment.
