Answer:
The fourth plant that receives pure water is the control group.
Explanation:
The election of a control group is essential in an experiment. Its principal purpose is to allow the discrimination of the results obtained by the treatment in the study, in this case, <em>the different concentrations of salty water that each plant receives</em>. The control group provides a reference point. It must be selected from the same population of the treatment groups. Both groups must be similar in every variable that might influence the results, <u>except for the study treatment.</u>
Answer:
Iron -> Fe - Group 8
Silver -> Ag - Group 11
Mercury -> Hg - Group 12
Oxygen -> O - Group 16
Gold -> Au - Group 11
Potassium -> K - Group 1
Xenon -> Xe - Group 18
Magnesium -> Mg - Group 2
Hydrogen -> H - Group 1
<span>Gregor Mendel was one of the first scientists to use numbers to look for patters in experimental data. </span>
