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Experimental Design PracticeA student performed an experiment to determine the effect of acid rain on plant growth. The student divided 80 seeds of a fast-growing plant species into four groups of 20 seeds each. The four groups of seeds were then planted in soil. After all of the seeds germinated in the same growing conditions, they were watered once a day with simulated rainwater that had different levels of acidity. The acidity of the four different watering solutions was as follows: neutral water, 0.1%, 1.0%, and 10%. The average height of the plants in each group was measured over a two-week period. (Sound familiar? Our poor radishes)1. State a valid hypothesis for the experiment.acid rain affects the growth of plants.2. Identify the control groupNeutral water3. Identify the independent variableThe acidity of the water.4. Identify the dependent variableThe growth of the plants. - average height 5. Describe results that would support your hypothesis.If the plant with the water solution with 10% acidity has the lowest plant growth, then it is shown how acid rain negatively affects the growth rate on plants.6. The experiment was repeated and each soil had the addition of crushed limestone. Describe how the modificationto the experiment would affect the results. The limestone can be used as a neutralizer or absorbant that will affect how the acid rain reacts with the plants.