Answer:
Iron is a major component of red blood cells. The oxygen you breathe bonds to the iron in your red blood cells. If you had no iron in your body you would likely die.
A control group of the experiment is the one in which no treatment or intervention is given. So, in your case, the pea plants in which was not subjected any of the fertilizers, will serve as a control group. This is a negative control. A positive control group is the one in which an established treatment is given, which definitely leads to the production of the desired character. So, in your case, a very good well-known fertilizer which has a positive control on the growth of the pea plant, would serve as a positive control.
Answer:
Filtering to obtains breadcrumbs and the heat the salt solution to saturation and cool it
