Question

Pleeeeeeeeeeeeeeeeeeeeeeease Help!

Answer 1

One student did an experiment to find if fertilizer can make plants grow taller. The steps of the experiment are listed below.

Take three pots of different sizes.
Fill the pots completely with the same type of soil.
Plant tomato seeds in the pots of soil.
Add different amounts of fertilizer to the three pots.
Keep the pots in the sunlight.
Add the same amount of water to the pots every day.
Measure the heights of the plants after regular intervals.
The results of the experiment were not valid. Which of these statements best describes a flaw in the experiment?
The amount of fertilizer was not the controlled variable.

The amount of soil in the pots was not the controlled variable.

The increase in height of plants was the dependent variable.

The increase in height of plants was the independent variable.

Answer 2

The results of the experiment were not valid because the amount of fertilizer was not the controlled variable. You want everything to be the same in the experiment except on change and because there are two changes in the experiment, the results are not valid. In order for the amount of fertilizer to be a controlled variable, the three pots must be of the same size. I hope this helps :).