Final Answer:
The independent variable in each experiment was the type of fertilizer used, and the dependent variable was the plant growth measured in height.
Step-by-step explanation:
In experimental design, the independent variable is the factor that is deliberately manipulated or changed by the researcher. It is the presumed cause and is often found on the x-axis of a graph. In this scenario, the type of fertilizer represents the independent variable as it is intentionally varied to observe its effect on the plants.
The dependent variable, on the other hand, is the observed result or outcome that is affected by the independent variable. It is the variable that is measured and recorded during the experiment and typically found on the y-axis of a graph. In this case, plant growth, specifically measured in height, serves as the dependent variable. The growth of the plants is influenced by the type of fertilizer applied.
To clarify, when conducting the experiment, various types of fertilizers are applied to different groups of plants while keeping other variables constant. The subsequent measurement of plant height allows the researcher to assess how the independent variable (type of fertilizer) impacts the dependent variable (plant growth). This experimental setup enables the identification of patterns or trends that help draw conclusions about the relationship between the chosen fertilizers and plant growth.