A neutron has zero charge but their mass is <span>1.67492716 × 10^-27 kg </span>
<span>Astronomers are able to determine facts about the composition of these moons by examining the nature of light that is reflected from their surfacy using a method called spectroscopy. This process works because different materials tend to reflect light at different wavelengths So, by observing at which wavelengths a planetary body reflects light, astronomers are able to estimate its composition.</span>
The second one since convection is the process by which heat is transferred from a solid surface to a non solid
Your variables would be varied temperature while your constants should be everything else (water, soil, proximity). Therefore, you can test for one variable (temperature difference) without muddling the results