To test how fertilizer affects aquatic animals, a student prepared four identical containers with water fleas. the student then added different amounts of fertilizer mixed with distilled water to three of the containers and distilled water alone to one of the containers. what is the control group in this experiment?

The control group in the given experiment would be the container to which only distilled water is added.  

In the given test done by the student, the amount of fertilizer is the factor, which is being tested in the experiment. In the mentioned experiment, distinct concentrations of fertilizer, which was mixed with distilled water were supplemented to three of the containers.  

The different concentration of the used fertilizer is anticipated to possess a distinct influence and to generate distinct outcomes. This makes the concentration of fertilizer to be the factor, which is being examined in the experiment. The container to which only distilled water is supplemented will function as the control in the experiment.

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explanation:

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.