B. One
I believe that earth is the only planet that has life that we know of on it.
Answer:
Orbitals
Shells
Energy Levels
Explanation:
Elements in the same period will have the same energy levels which is the same as orbitals and shells.
- The period of an element indicates the energy level in an atom.
- Elements in period 1 will have one energy level or shell or orbitals.
- Down a group this is not the case.
- The energy level increases from top to bottom.
- As we go down the group, we are transiting from one period to another.
Frequency is a measure of hertz
You are testing which fertilizer makes the radishes grow the fastest.
factors you should control: sunlight exposure, water amount, fertilizer amount.
Measure: check the rows of radishes to see how much each row has grown in comparison to the others. Whichever row with the healthiest radishes has the best fertilizer.
