Question

Dieffenbachia plants usually grow well without fertilizer. A student wanted to see if adding liquid fertilizer would make a difference in the growth of the plant. Three plants were placed in the same type of pot with the same type of soil. Two plants received fertilizer and one plant did not. All plants received the same amount of light and water during the experiment.She watched the plants grow over a period of 30 days, only adding the same amount of water to each plant on a weekly basis.

Answer 1

The question is incomplete. The complete question is as follows:

Dieffenbachia plants usually grow well without fertilizer. A student wanted to see if adding liquid fertilizer would make a difference in the growth of the plant. Three plants were placed in the same type of pot with the same type of soil. Two plants received fertilizer and one plant did not. All plants received the same amount of light and water during the experiment.She watched the plants grow over a period of 30 days, only adding the same amount of water to each plant on a weekly basis. What variable is NOT being controlled in this experiment?

Answer:

Amount of fertilizers.

Explanation:

Fertilizers may be defined as the chemicals that are required to increase the quality and quantity of the crops. The chemical fertilizers may cause environment pollution.

The experiment given in the question explains the different conditions at which the plant was grown. The controlled variable is the substance whose value is known and being constant in the experiment. In this experiment, the fertilizer is randomly given to the plant and its value is unknown. So we can say that the fertilizer is not a controlled variable in the experiment.

Thus, the correct answer is amount of fertilizers.

Answer 2

Answer:

amount of Liquid fertilizer

Explanation:

Complete Question

Dieffenbachia plants usually grow well without fertilizer. A student wanted to see if adding liquid fertilizer would make a difference in the growth of the plant. Three plants were placed in the same type of pot with the same type of soil. Two plants received fertilizer and one plant did not. All plants received the same amount of light and water during the experiment.She watched the plants grow over a period of 30 days, only adding the same amount of water to each plant on a weekly basis. What variable is NOT being controlled in this experiment?

Solution

In an experiment the variables are categorized into two groups  

a) Controlled and  

b) Uncontrolled  

Uncontrolled variable are the ones which are independent i.e any kind of  variation in experiment or any of its factor does not impact the uncontrolled variable. Such variable when in itself are varied, affect all other controlled variable.  

Thus, amount of liquid fertilizer is an uncontrolled variable while factors such as growth of plant etc. are controlled variable.