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.
Answer:
In animals, oxygen combines with food in the cells to produce energy for daily activity and then gives off carbon. The carbon combines with oxygen to form carbon dioxide (CO2) and is released back into the atmosphere as a waste product when animals breathe and exhale.
The first answer is volcanoes
The second answer is They move because of convection currents in the mantle
Proteins is a main source of energy that transports nutrients through your body, provides structure, and acts as a messenger via the circulatory system.