The simplest and most helpful visual aid for this experiment would be if the student sets rulers of some sort or maybe pieces of wood that are properly marked with certain measuring unite. If they are set right next to each plant, the student will be able to monitor constantly how are the plants growing, and the smaller the measuring unites the better, as the student will be able to monitor the situation in higher detail.
Over time, the plants will most surely develop differently, so the student will have it easier to notice the changes. Considering that it is an experiment in question, the student should use proper measurements and to be able to have detailed numbers for it.
Answer
Electrons live inside the nucleus and carry a neutral charge.
Explanation:
A, as carbon is an atomic substance - element
<u>Answer:</u> The edge length of the unit cell is 0.461 nm
<u>Explanation:</u>
We are given:
Atomic radius of iridium = 0.163 nm
To calculate the edge length, we use the relation between the radius and edge length for FCC lattice:

Putting values in above equation, we get:

Hence, the edge length of the unit cell is 0.461 nm
I also think it’s B but not quite sure