Answer :
Answer No 1)
The purpose of the lab was to test the effects of different fertilizers on the growth of plant.
The hypothesis was that if organic fertilizers are used, they could make the plants grow taller.
The independent variables will be the different fertilizers which were being used. The dependent variable will be the growth or height of the plants. The controlled variable will be the plants to which no fertilizers will be added.
Answer No 2)
The hypothesis proposed by John was wrong. John proposed that the plants who were given organic fertilizers will grow the most. On the other hand, when experiments were performed plants which were given chemical fertilizers grew more as compared to the plants which were given organic fertilizers.
Answer No 3)
We can improve the experiment by checking out more number of plants instead of just one plant for each category. fertilizers also. This is because using only one plant for each category might not have provided the best authentic results. The experiment can be beneficial as it will allow the usage of fertilizers which will give enhanced growth in plants.