The second one since you’re changing the soil up by adding different fertilisers. This will be you’re independent variable. And you’re dependent variable is your result = the plant height .
Hope this helps :)
The food you eat every day provides the nutrients you need to survive. These food components include the macronutrients – protein, carbohydrate and fat – that offer calories as well as play specific roles in maintaining your health. Micronutrients, such as vitamins and minerals, don’t act as an energy source but do serve a variety of critical functions to ensure your body operates as optimally as possible.
