Answer:
Option 3 is correct.
The atomic nucleus of each element has a unique number of protons. Therefore, the energy of the electron layers of the atoms of each element is unique.
If we have the energy released from each electron transfer between the layers of the atom, we can identify the element.
I believe the answer would be:
A. Three groups of plants—a group fertilized by X, a group fertilized by Y, and a control group with no fertilizer.
I hope this helps.
Answer:
Explanation:
An<u> independent variable</u> is the variable that is intentionally altered or changed during the course of an experiment and is not dependent on another variable. The independent variable from the narration in the question is the different types of plants (as seen, the type of plant was intentionally changed during the course of the experiment).
A <u>dependent variable</u> is the variable whose "outcome" is assumed/expected to be dependent on another variable called the independent variable. The dependent variable from the narration in the question is the number of flowers (as seen, the outcome/number of flowers is expected to be dependent on the type of plant).
The <u>control group</u> is the group that is used as a reference (or benchmark) for the sake of comparisons while reporting an experiment. From the narration in the question, nothing was mentioned as regards the control group.
<u>Constants</u> are unchanged factors that are maintained throughout the course of an experiment. From the narration, the constant is the time in which her observations are done which is weekly (every week).