Answer:
Explanation:
the heart pumps blood throughout the body, and the lungs aid in breathing. the body parts that are found on frog are the heart, the liver, and the stomach, etc.
The only independent variable in this experiment is the amount of nitrogen Sarah uses. All of the other variables are dependent on other factor and processes, but Sarah controls the amount of nitrogen that she uses for each plant.
Answer:
I think you answered your own question
